What causes a low-grade fever in adults. How long should a mild fever last. When does a fever become dangerous for adults. What are the best ways to treat a low-grade fever at home. How can you tell if a fever is a sign of a serious infection.

Understanding Low-Grade Fevers: Causes and Symptoms

A low-grade fever is a body temperature that falls between your normal body temperature and 100.4°F (38°C). While there’s some debate among medical professionals about the exact definition, most consider a low-grade fever to be a slight elevation in body temperature that doesn’t quite reach the threshold of a full-blown fever.

Common causes of low-grade fevers include:

• Viral infections like the common cold or flu
• Bacterial infections such as urinary tract infections
• Mild cases of pneumonia
• Sinus infections
• Gastrointestinal viruses
• Food poisoning

In addition to an elevated temperature, symptoms accompanying a low-grade fever may include:

• Mild chills
• Slight sweating
• Headache
• Flushed face
• General discomfort

The Body’s Natural Defense: How Fevers Work

Why does our body temperature rise when we’re sick? A fever is actually a defense mechanism employed by our immune system. By increasing body temperature, the body creates an environment that’s less hospitable to invading pathogens, making it harder for them to survive and reproduce.

In the case of a low-grade fever, this slight temperature elevation often indicates that your body is in the early stages of fighting off an infection. It’s your immune system’s first line of defense, working to eliminate the threat before it can take a stronger hold.

When Is a Low-Grade Fever Cause for Concern?

Generally, a low-grade fever alone isn’t a reason to worry. However, there are certain situations where it might indicate a more serious condition. Pay attention to these factors:

Duration of the Fever

How long should a mild fever last before you should be concerned? If a low-grade fever persists for more than three days, it’s advisable to consult a healthcare provider. Prolonged fevers can be a sign of a more severe underlying condition.

Accompanying Symptoms

Are there any symptoms that, when combined with a low-grade fever, should prompt immediate medical attention? Yes, if you experience any of the following along with your fever, seek medical help:

• Severe headache
• Stiff neck
• Confusion or altered mental state
• Difficulty breathing
• Severe abdominal pain
• Unexplained rash

Rapid Temperature Increase

If your low-grade fever quickly escalates to a high fever (above 103°F or 39.4°C), this could indicate a more serious infection and warrants medical evaluation.

Home Remedies and Treatment for Low-Grade Fevers

In most cases, low-grade fevers can be managed effectively at home. Here are some strategies to help alleviate symptoms and support your body’s healing process:

Rest and Hydration

Getting plenty of rest allows your body to focus its energy on fighting the infection. Staying well-hydrated is crucial, as fevers can lead to increased fluid loss through sweating. Drink water, herbal teas, or clear broths regularly.

Over-the-Counter Medications

Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can help reduce fever and alleviate associated discomfort. However, it’s important to note that you don’t necessarily need to take medication for a low-grade fever unless you’re experiencing significant discomfort.

Cool Compresses

Applying a cool, damp cloth to your forehead or wrists can help provide relief and may help lower your body temperature slightly.

Dress Comfortably

Wear light, breathable clothing and use lightweight bedding to avoid overheating.

Monitoring Your Fever: Tips and Techniques

Keeping track of your fever is an important part of managing your health during an illness. Here are some tips for effective fever monitoring:

Choose the Right Thermometer

Digital thermometers are generally the most accurate and easiest to use. You can take your temperature orally, rectally, or in your armpit, with oral readings being the most common method for adults.

Timing Matters

Body temperature naturally fluctuates throughout the day, typically being lowest in the early morning and highest in the late afternoon. For consistent readings, try to take your temperature at the same time each day.

Keep a Fever Log

Record your temperature readings along with the time and any accompanying symptoms. This information can be valuable if you need to consult a healthcare provider.

When to Seek Medical Attention for a Fever

While most low-grade fevers aren’t cause for alarm, there are situations where professional medical advice is necessary. Contact your healthcare provider if:

• Your fever persists for more than three days
• Your temperature exceeds 103°F (39.4°C)
• You experience severe symptoms alongside your fever
• You have a compromised immune system
• You’ve recently traveled to an area with known infectious disease outbreaks

Remember, it’s always better to err on the side of caution when it comes to your health. If you’re unsure about the severity of your condition, don’t hesitate to reach out to a medical professional.

Fevers in Special Populations: Considerations for Certain Groups

While we’ve primarily discussed fevers in general adult populations, it’s important to note that certain groups may need to approach fever management differently:

Older Adults

Older adults may not develop fevers as readily as younger individuals, even when fighting infections. This means that even a slight elevation in temperature could be significant. If you’re over 65 and develop a fever, it’s advisable to consult with a healthcare provider.

Immunocompromised Individuals

People with weakened immune systems, such as those undergoing chemotherapy or living with HIV, may be more susceptible to infections. Any fever in these individuals should be taken seriously and evaluated by a medical professional.

Pregnant Women

Fever during pregnancy can potentially affect fetal development. Pregnant women with fevers should consult their obstetrician or midwife for guidance on safe fever management.

Beyond Infections: Other Causes of Low-Grade Fevers

While infections are the most common cause of low-grade fevers, there are other factors that can elevate body temperature:

Physical Exertion

Intense exercise or prolonged physical activity can temporarily raise your body temperature. This exercise-induced elevation typically resolves within a few hours of rest.

Environmental Factors

Exposure to hot weather or wearing heavy clothing in warm environments can lead to a slight increase in body temperature. This is your body’s natural response to prevent overheating.

Autoimmune Disorders

Certain autoimmune conditions, such as rheumatoid arthritis or lupus, can cause low-grade fevers as part of their symptom profile.

Medications and Vaccines

Some medications and recent vaccinations can cause a temporary elevation in body temperature as a side effect.

Stress

In some cases, significant emotional or physical stress can lead to a slight increase in body temperature.

Understanding these non-infectious causes of low-grade fevers can help you better interpret your symptoms and decide whether medical attention is necessary.

The Role of Fever in Healing: Friend or Foe?

Is a fever always a bad thing? Contrary to popular belief, a fever isn’t necessarily an enemy to be defeated. In fact, it plays a crucial role in the body’s defense against pathogens.

Benefits of Fever

A fever can:

• Slow down the reproduction of bacteria and viruses
• Enhance the activity of white blood cells
• Stimulate the production of disease-fighting substances in the body

This is why some medical professionals advise against immediately treating low-grade fevers with fever-reducing medications, unless the fever is causing significant discomfort or putting the patient at risk.

When Fever Becomes Harmful

However, there’s a point at which the drawbacks of a fever outweigh its benefits. Very high fevers (above 104°F or 40°C) can lead to complications such as dehydration, confusion, and in extreme cases, organ damage. This is why it’s crucial to monitor fevers closely and seek medical attention when they become severe.

Understanding the dual nature of fever – both as a healing mechanism and a potential threat – can help you make informed decisions about when to treat a fever and when to let it run its course under careful observation.

What Is a Low-Grade Fever? Causes, Symptoms, and Treatment

• A low-grade fever happens when your body temperature is elevated, but still under 100.4°F. 
• Some causes of a low-grade fever include the common cold, the flu, a stomach virus, or a UTI.
• But a low-grade fever in itself isn’t necessarily a reason to worry, since a slightly elevated temperature won’t hurt your body. 

Many illnesses can cause a fever, which is when your body temperature rises over 100.4°F. In some cases, your body temperature may be elevated, but not quite as high as a fever. This is often referred to as a “low-grade fever” although it does not technically meet the definition of a fever. 

Most of the time, low-grade fevers aren’t a reason to worry. Many everyday ailments can cause a low-grade fever, including an ear infection or stomach bug. In rare cases, you can also have a low-grade fever with more serious infections.

Here’s what you need to know about how to treat low-grade fevers and when you need to see a doctor. 

What is a low-grade fever?

A low-grade fever is a body temperature that runs somewhere between your normal body temperature and 100.4°F, says Troy Madsen, MD, a professor of emergency medicine at the University of Utah.

However, there is some debate in the medical field about the exact body temperature that counts as a fever. “The definition may vary between 100.4 and 100.5 depending on the medical provider and the institution,” Madsen says.

There is also some debate about the existence of a low-grade fever. While some providers accept the definition of a low-grade fever as anything between normal body temperature and 100.4°F, other providers believe that your temperature must be above 100.4°F to even count as a fever. 

Your body temperature can shift based on factors like your age or the time of day, but for most people, a normal temperature falls anywhere between 97 and 99°F.

But when you get sick, your body heats up and develops a fever to make it harder for any disease cells to survive in your body. A low-grade fever can be a sign of an infection beginning in your body. 

What causes a low-grade fever? 

“The same infections which cause a typical fever may cause a low-grade fever, particularly if it’s in the early stages of the infection,” Madsen says. 

Some infections that can cause a low-grade fever include:

• A common cold virus
• A urinary tract infection
• The flu
• Pneumonia
• A sinus infection
• A stomach virus
• Food poisoning

If you have a severe infection like meningitis, your fever generally won’t stay at the low-grade level for long. “In most cases, a serious infection will progress from a low-grade fever to a temperature of 100.5°F or greater within a day,” Madsen says.

But infections aren’t the only cause of low-grade fevers. There are several other reasons you may run a low-grade fever, such as:

• You’re exercising vigorously.
• You’re outside in hot weather or wearing heavy clothing.
• You have an autoimmune disorder like rheumatoid arthritis.
• You have recently had a flu vaccine.
• You’re feeling especially stressed.

In these situations, a rise in body temperature is a normal response and usually isn’t a cause for concern, Madsen says. Along with a low-grade fever, you might sweat, have slight chills, develop a headache, or have a flushed face.

But if your low-grade fever comes with symptoms like extreme fatigue or confusion, this may be a cause for concern, Madsen says. 

How to treat a low-grade fever

A low-grade fever in itself isn’t necessarily a reason to worry, Madsen says, because a slightly higher temperature won’t hurt your body.

But low-grade fevers can come with some uncomfortable symptoms that you may want to treat. “For example, you may have the early stages of a cold or the flu and have a low-grade fever with body aches and a sore throat,” Madsen says.

Taking a dose of a non-steroidal anti-inflammatory drug like ibuprofen can help treat these symptoms and bring your temperature down as well. However, it’s not necessary to take any medications unless your fever rises over 102°F.

If your low-grade fever is due to overheating, putting on loose-fitting clothing, resting in a cool space, or taking a cold shower may help bring your body down to a normal temperature.

No matter what is causing your fever, it’s important to drink plenty of fluids. A low-grade fever generally won’t cause severe dehydration, but you lose fluids more easily when your body temperature is higher. Drinking cold fluids can also help lower your body temperature.

 It’s also important to keep monitoring your temperature to see if it rises above 100. 5 degrees and becomes an actual fever. You can take your temperature using a thermometer orally, rectally, or in your armpit.

When to see a doctor

“A low-grade fever in itself doesn’t necessarily mean you need to see a doctor,” Madsen says, “But if you’re having other symptoms plus an elevated body temperature it may be a good time to call your doctor.”

Be on the lookout for symptoms of an infection, as a bacterial infection may need to be treated with antibiotics. Madsen advises that some symptoms to look out for are:

• Burning with urination
• Difficulty breathing
• Persistent cough
• Congestion that doesn’t improve after a week 
• Rash
• Severe headache

For most adults and children, you should call your doctor if your temperature rises above 103°F. If you have an infant under 3 months old, you should call the doctor if their temperature rises above 100. 4°F.

In very rare cases, people may run low-grade fevers for weeks or months, Madsen says. You shouldn’t ignore this symptom, as it can be a sign of a cancer like lymphoma.

“If your body temperature just seems to be abnormally high over a longer period of time, it’s a good idea to check in with your doctor, particularly if you’re experiencing unexplained weight loss or extreme fatigue,” Madsen says.

Insider’s takeaway 

A low-grade fever is a body temperature between 99 and 100.5°F. In most cases, a low-grade fever isn’t anything to worry about and you can get relief from any symptoms by taking ibuprofen or drinking cold water. 

However, if your fever keeps rising or you develop any unusual symptoms, reach out to your doctor to check that you don’t have an infection or any other serious medical issue.

• What causes a fever and when to seek medical attention
• How to break a fever and help alleviate your symptoms
• What is normal body temperature? How to know if you have a fever
• You’re probably not washing your hands long enough, and it could be making you sick
• Vitamin C for the common cold is a myth, sort of

Madeline Kennedy

Madeline Kennedy is a health writer for Insider covering a wide range of topics including reproductive and sexual health, mental health, nutrition, and infectious disease. Before joining Insider, Madeline worked as a health news writer for Reuters, and a domestic violence therapist. She has a master’s degree in social work from UPenn and is interested in the intersection of health and social justice.

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What Is a Low-Grade Fever? Causes, Symptoms, Treatment │ Vicks

Achy, tired, warm skin, and just not feeling right? You may have a low-grade fever. Before you figure out how to treat your low-grade fever, understand where it might have come from and what role it plays in your body.

Your body is a complex and smart system that constantly works to keep you feeling your best, including maintaining the optimum internal temperature. Your internal temperature is subject to hormonal and brain activity and adapts to conditions of your environment. For your body to work properly, your optimum body temperature is 98.6°F (37°C).¹ Sometimes, though, your body needs to elevate its temperature above that ideal level to, for example, fight off a cold or flu virus. In those cases, you might experience a low-grade fever.

Fevers are common, and they occur for a variety of reasons, often signaling that the body is working to protect itself.^2,4,5

Fevers happen for a variety of reasons and at different severity levels. Depending on your specific temperature, your fever may be categorized as low-grade fever, regular fever, or high-grade fever. The use of these terms highlights the importance of monitoring a fever.

What is a Low-Grade Fever?

A low-grade fever refers to a temperature slightly above what is considered a normal temperature. There is no standard for the specific temperature range corresponding to low-grade fever.

Regardless of the specific range that may be used to define a low-grade fever, the unifying factor for all low-grade fevers is that they represent temperatures above the ideal temperature but below what would be considered a fever.⁸

Some experts define a low-grade fever as a temperature that falls between 99. 5°F (37.5°C) and 100.3°F (38.3°C).^6,7 According to the U.S. Centers for Disease Control and Prevention (CDC), a person with temperature at or above 100.4°F (38°C) is considered to have a fever.³

What Causes a Low-Grade Fever?

Low-grade fevers can occur for several reasons and may be accompanied by other symptoms.⁹Colds and flus, for instance, are major contributors to fevers. Fevers occur more often in those who suffer from flus than in those who suffer from colds.¹⁰ However, fevers that occur in colds are more likely to be low-grade fevers, whereas fevers that occur with the flu can be low-grade or more severe.

Signs and Symptoms of Low-Grade Fever

The easiest way to determine if you have a low-grade fever—or any fever—is to simply take your temperature. However, in addition to a raised temperature, there are other signs of fever, like:³

• Warm skin
• A flushed face
• Glassy eyes
• Chills or Shivering
• Sweating
• Headache
• Muscle Aches

Depending on the underlying cause of the low-grade fever, the fever may also present with other symptoms, such as symptoms that commonly occur with fever-causing viruses like colds and flus. These symptoms—which may include coughs, sore throats, headaches, or other symptoms—can be used to help determine the reason for the fever and the best way to treat it.

How to Treat a Low-Grade Fever

The recommendations for treating a fever vary, and in the case of a low-grade fever, there are several things you can do to make yourself feel better if you are uncomfortable.¹¹ Some of these options are to:

• Rest¹²
• Drink fluids¹²
• Call a doctor if your fever is accompanied by a severe headache, stiff neck, shortness of breath, or other unusual signs or symptoms.
• Place a cold, damp washcloth on your forehead or the back of your neck while you’re resting.
• Take over-the-counter medication to treat the symptoms associated with your fever. Many over-the-counter cold and flu medicines treat multiple symptoms. Identify what other symptoms you are experiencing with a low-grade fever, if any, so you can choose a medicine that gives the relief you need. Medicines that contain acetaminophen help reduce fever. Some medicines with this active ingredient include:
• DayQuil and NyQuil: These liquid multi-symptom products also treat symptoms associated with the cold or flu, like cough, sore throat, and more. They also come in LiquiCap™ form.
• DayQuil and NyQuil SEVERE: For relief of even more symptoms, try NyQuil SEVERE, which can also help with nasal congestion, or DayQuil SEVERE, which contains an expectorant to help loosen mucus and make coughs more productive.
• FluTherapy Day and Night: Drink in tasty honey lemon flavor and breathe in the soothing Vicks Vapors. Cold and flu symptom relief—including fever—can come as a comforting medicated hot drink, too, with Vicks FluTherapy.

Consult your doctor if you are experiencing any of the below:¹³

• If your temperature reaches 104° F or higher.
• If you have fever or cough symptoms that improve, then get worse.
• If your fever is accompanied by a severe muscle pain, mental confusion, or any other out-of-the ordinary symptoms.

Low-grade fevers can come from common viruses like a cold or the flu. Taking your temperature is the easiest and most direct way to determine if you have a low-grade fever, but other signs and symptoms can also point to an increased likelihood that you are experiencing a low-grade fever.

Maintaining your health through good habits such as getting enough rest and fluids can help to minimize a fever or to reduce its duration by, for instance, supporting your immune system. In the case that you opt for medication to help relieve symptoms and reduce a low-grade fever, consider appropriate options that contain acetaminophen, a fever reducer, like DayQuil, NyQuil, and FluTherapy.

Take care of yourself, and feel better soon!

1. How is body temperature regulated and what is fever? nih.gov. https://www.ncbi.nlm.nih.gov/books/NBK279457/. Published 2009. Accessed June 11, 2020.

2. Soszyński D. [The pathogenesis and the adaptive value of fever]. Postepy Hig Med Dosw. 2003;57(5):531-554.

3. Reporting: Symptoms definitions. cdc.gov. https://www.cdc.gov/quarantine/air/reporting-deaths-illness/definitions-symptoms-reportable-illnesses.html. Accessed June 11, 2020.

4. Torreggiani S, Filocamo G, Esposito S. Recurrent Fever in Children. Int J Mol Sci. 2016;17(4):448. doi:10.3390/ijms17040448

5. Moltz H. Fever: causes and consequences. Neurosci Biobehav Rev. 1993;17(3):237-269. doi:10.1016/s0149-7634(05)80009-0

6. Thompson HJ. Fever: a concept analysis. J Adv Nurs. 2005;51(5):484-492. doi:10.1111/j.1365-2648.2005.03520.x

7. Affronti M, Mansueto P, Soresi M, et al. Low-grade fever: how to distinguish organic from non-organic forms. Int J Clin Pract. 2010;64(3):316-321. doi:10.1111/j.1742-1241.2009.02256.x

8. Chughtai AA, Wang Q, Dung TC, Macintyre CR. The presence of fever in adults with influenza and other viral respiratory infections. Epidemiol Infect. 2017;145(1):148-155. doi:10.1017/S0950268816002181

9. McGregor AC, Moore DA. Infectious causes of fever of unknown origin. Clin Med. 2015;15(3):285-287. doi:10.7861/clinmedicine.15-3-285

10. The difference between cold and flu. CDC.gov. https://www.cdc.gov/flu/symptoms/coldflu.htm. Accessed June 9, 2020.

11. El-Radhi ASM. Fever management: Evidence vs current practice. World J Clin Pediatr. 2012;1(4):29-33. doi:10.5409/wjcp.v1.i4.29

12. Fever treatment: Quick quide to treating a fever. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/fever/in-depth/fever/art-20050997. Accessed June 11, 2020.

13. Flu: What to Do if You Get Sick. cdc.gov. https://www.cdc.gov/flu/treatment/takingcare.htm. Accessed June 26, 2020.

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Temperature of 37.3 °C for colds, flu and SARS – causes and treatment

A slight increase in body temperature during a cold, although it causes weakness or fatigue, does not pose a serious danger ⁴ .

An increase in body temperature is a protective reaction of the body ³ , it helps the body fight infectious agents ^3.4 .

That is why it is possible to perceive fever as a negative phenomenon only if it is poorly tolerated, combined with “ache” in the body, or the mark on the thermometer reaches 38 ° C ^6.7 .

Fever develops as a result of exposure to the thermoregulatory center of pyrogens. Pyrogens are substances that cause a rise in body temperature ³ . Their role is often played by infectious agents – viruses, bacteria and other microorganisms, and fever can also be caused by pyrogens, which are formed in the body itself when various organs malfunction, inflammatory and allergic processes ³ .

Pyrogens that appear in the body are carried with the blood to all organs. They reach the brain and trigger processes in it that lead to a decrease in the sensitivity of the thermoregulation center. As a result, the internal thermostat changes the setpoint and begins to perceive normal body temperature as low ⁴ .

In order to “correct” the situation, it enhances the processes of heat production and inhibits heat transfer ⁴ :

• for the rapid production of thermal energy, muscle tremors are activated;
• To reduce heat loss, superficial skin vessels contract.

The skin becomes pale and cold to the touch ⁴ , and a decrease in skin temperature creates a new flow of impulses – already in the direction from the skin to the thermoregulation center. The latter, receiving signals from the skin, again raises the body temperature ⁴ . The result of this stimulation of the internal thermostat is a second revision of the settings and a new round of temperature increase ⁴ .

Fever is good for the body, it ⁴ :

• stimulates the activity of cells of the immune system;
• inhibits the reproduction of many viruses and bacteria;
• helps cleanse the body of toxins;
• increases the body’s overall resistance to infections.

The fever persists until the amount of pyrogens in the body begins to decrease, that is, until the healing process begins ⁴ .

Despite the positive effects, subfebrile fever requires attention, since it can be a manifestation of hidden processes and serious diseases, such as tuberculosis or malignant diseases ³ .

A temperature of 37.3°C may be due to overheating, or, scientifically, hyperthermia ³ . Its difference from fever is that the body temperature rises without changing the set point of the thermoregulatory center. When overheated, the balance between heat transfer and heat production is not related to pyrogens ^{2. 3} . Causes of hyperthermia can be severe stress ⁴ , heat stroke ³ or dehydration ⁴ .

Adults have “workday hyperthermia” ² . Its peculiarity is that the body temperature rises only on those days when you need to go to work, on weekends it remains normal ² . Unlike catarrhal fever, such hyperthermia does not affect the state of health, is not accompanied by chills and disappears without a trace at night, when the nervous system is resting ² .

Do not try to figure out the cause of the temperature rise to 37.3 °C on your own. To understand what exactly subfebrile condition is connected with, you need to consult a doctor, tell him in as much detail as possible about the situation when subfebrile condition appeared, and undergo the necessary examination. After the examination, the doctor will prescribe a treatment that will help normalize the temperature and eliminate the cause of the fever.

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Influenza – Articles for the population – Khislavichskaya district hospital

May 11

Influenza is an acute highly contagious disease that is characterized by severe toxicosis, moderate catarrhal phenomena with the most intense damage to the trachea and large bronchi. The clinical symptoms of influenza can vary significantly depending on the state of the body’s defenses and the age of the patient, the contagiousness of the virus and its type. Influenza can be uncomplicated and complicated.
According to the severity of the course, influenza is divided into:
• mild form
• medium form
• severe form
• hypertoxic form
• fulminant form of the course.
The incubation period for influenza typically ranges from a few hours to 1-2 days, but can be as long as 5 days.
Then begins the period of acute clinical manifestations of influenza. The severity of uncomplicated influenza is determined by the severity and duration of intoxication.
The syndrome of intoxication is the leading one in influenza and is expressed from the very first hours of the disease. The first sign of the flu is a fever. Influenza always begins acutely with an increase in body temperature – from subfebrile figures to hyperthermia (from 37.2 to 40 ° Celsius). Usually within a few hours the temperature reaches high numbers and is accompanied by chills. With a mild course of the disease, the body temperature does not exceed subfebrile numbers. The level of fever reflects the severity of intoxication, but these concepts cannot be completely identified. Sometimes at a very high body temperature, the signs of intoxication are not pronounced, which is often observed in young people with influenza caused by type A (h2N1) virus! Their temperature rise is short-term, and then the disease has a moderate course.
The temperature reaction in influenza is acute and relatively short-lived. The feverish period lasts 2-6 days, rarely longer, and then the temperature drops rapidly. The presence of prolonged fever may indicate the occurrence of any complication.
The leading sign of intoxication and one of the first signs of flu symptoms is a headache. Pain is noted in the frontal region, especially in the region of the superciliary arches, in the supraorbital region, sometimes behind the orbits of the eyes and increases with the movement of the eyeball. Headaches are common in older people. The severity of the headache can vary, but in most cases it is mild. Severe headache in combination with sleep disturbance, repeated vomiting, hallucinations is observed in patients with a severe course of the disease and is often accompanied by a syndrome of damage to the central nervous system. In adults, unlike children, a convulsive syndrome occurs abruptly.
General weakness, feeling unwell, weakness, increased sweating are common symptoms of influenza. There is an increased sensitivity to bright light, sharp sounds, to cold. Consciousness is often preserved, but delusional states are possible. A frequent symptom of the flu is muscle and joint pain, aches throughout the body, mainly in the lumbosacral region.
The appearance of the patient is characteristic: the face is reddened, puffy. Conjunctivitis is noted, which is accompanied by photophobia and lacrimation. Due to impaired capillary circulation and hypoxia, the patient’s face has a bluish tint.
Catarrhal syndrome is also one of the leading in influenza infection, but it recedes into the background and in some cases is weakly expressed or absent. The duration of the catarrhal syndrome is 7-10 days. The cough lasts the longest.
In the first days there are changes in the oropharynx: pronounced reddening of the soft palate with a clear distinction from the hard palate. By 3-4 days from the onset of the disease, redness is replaced by an injection of vessels that form a plexus – a “mesh”. In addition, with a severe course of the disease, small hemorrhages appear in the soft palate. Against the background of vascular disorders, there is granularity, represented by enlarged lymphatic follicles. In severe influenza, in addition to swelling of the soft palate, cyanosis is noted. The back wall of the pharynx in patients with influenza is dryish, shiny, reddened, often grainy. Patients note perspiration and dryness in the throat. By 7-8 days from the onset of the disease, the mucous membrane of the soft palate in most patients acquires a normal appearance.
There are changes in the nasopharynx: the nasal mucosa is reddened, swollen, dry. Swelling of the turbinates makes it difficult to breathe through the nose. These changes on the 2-3 day from the onset of the disease are replaced by discharge from the nose. Rhinitis is observed in approximately 80% of patients, its duration is 4-7 days. Due to toxic damage to the walls of blood vessels and intense sneezing, influenza often causes nosebleeds.
The most typical syndrome is tracheobronchitis, which is manifested by soreness or pain in the chest, behind the sternum, as well as a painful dry cough.
Cough occurs in approximately 90% of patients. Duration of cough with uncomplicated influenza is 5-6 days. Increased breathing is possible, but the nature of breathing does not change.
Laryngitis (sore throat, hoarseness) with influenza is combined with tracheitis, and tracheitis prevails in the clinical picture. In children, influenzal laryngotracheitis can lead to croup.
Changes in the lungs correlate with the age of the patient, as well as with the presence of concomitant cardiovascular and pulmonary diseases. When listening to the lungs, hard breathing and short-term dry wheezing can be determined.
Changes in the cardiovascular system in influenza are due to toxic damage to the heart muscle. When listening to the heart, muffled tones are determined, sometimes a systolic murmur at the apex of the heart and a rhythm disturbance like extrasystole. At the onset of the disease, with an increase in body temperature, there is an increase in the pulse, which is accompanied by blanching of the skin. On the 2-3rd day, along with lethargy and weakness in the body, there is a decrease in the pulse, which is accompanied by reddening of the skin.
Changes in the digestive organs are not expressed. Often there is a decrease in appetite, intestinal motility worsens and constipation joins. The tongue is densely coated with white, not thickened. The abdomen is painless. What is known as “stomach flu” is not caused by the influenza virus at all. Short-term intestinal upset is associated with exacerbation of chronic gastrointestinal diseases.
Changes in the urinary system. Viruses excreted through the kidneys cause damage to the kidney tissue. These disorders may be accompanied by the appearance of protein and blood elements in urine tests. In the uncomplicated course of influenza, there are no violations of the kidneys and bladder.
Changes in the central nervous system. Toxic reactions from the nervous system can manifest as a sharp headache, aggravated by other external irritants. Excitation or, conversely, drowsiness may be observed. Vomiting, delirium, convulsions, loss of consciousness, fainting are possible. Meningeal symptoms are observed in 3% of patients.
Changes in peripheral blood – hemoglobin and red blood cell count do not change. The number of leukocytes increases and the ESR increases.
Clinical picture of influenza, taking into account the severity of the disease
In the case of mild (including erased and subclinical) forms of influenza, body temperature may remain normal or increase no more than 38 ° Celsius, symptoms of toxicosis are mild or absent.
In the moderate (manifest) form of influenza, the body temperature rises to 38.5-39.5 ° and classical symptoms of the disease are noted.
Intoxication: profuse sweating, general weakness, photophobia, headache, joint and muscle pain.
Catarrhal flu symptoms: redness of the soft palate and posterior pharyngeal wall, respiratory symptoms, redness of the conjunctiva, damage to the larynx and trachea, dry cough, voice disturbance, rhinitis, chest pain, redness or cyanosis and dryness of the mucous membrane of the nasal cavity and oropharynx.
In severe and extremely severe forms of influenza, a large number of painful symptoms are noted – from the usual severe course with severe symptoms of intoxication and catarrhal phenomena to the predominance of the highest degree of intoxication in the clinical picture, leading to the development of the syndrome of toxicosis of the central nervous system and swelling of the brain, damage to the heart vascular system and the development of infectious-toxic shock of varying severity.
With the development of a severe form of influenza, body temperature rises to 40-40.5 °. There are signs of encephalopathy (convulsions, hallucinations), vascular disorders (nosebleeds) and vomiting.
Respiratory failure leading to pulmonary edema and other complications may develop.
In the fulminant form of influenza, there is a serious risk of death, especially for debilitated patients and patients with various concomitant diseases. This form includes swelling of the lungs and brain, bleeding, the development of varying degrees of respiratory failure, and other serious complications.
If the flu proceeds without complications, the febrile period lasts 2-4 days and the disease ends within 5-10 days. Repeated rises in body temperature are possible, but they are usually due to the layering of some bacterial flora or other viral respiratory infection. Post-infectious asthenia may persist for 2-3 weeks after the flu: fatigue, general weakness, headache, irritability, sleep disturbance, etc.