TDAP vaccine: When to get it, side effects, and safety

Fever: What's Considered Low, High, And Possibly Serious?

Fever is an elevation in the body's temperature. It's not a disease but rather a sign or response to something occurring within the body, most commonly an infection. Noninfectious conditions or scenarios like inflammatory diseases or medication reactions can also cause a fever.

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What Is Considered a Normal Body Temperature? To understand fever, it's important first to understand what a normal body temperature is. Normal Body Temperature Ranges There is no formal definition for a normal body temperature, although general ranges exist. Factors affecting body temperature include age, measurement site (e.G., mouth vs. Rectum vs. Underarm), and time of day. Body temperature is naturally at its lowest in the early morning and highest in the late afternoon. In adults, the average body temperature measured orally (by mouth) is 98.0 F (36.7 C), with an approximate range between 95.5 F and 99.9 F. In most babies and children, the normal body temperature range is between 97.7 F (36.5 C) and 99.5 F (37.5 C). Their slightly higher body temperature is attributed to their greater total surface area in relation to their body weight and higher metabolisms. Measurement Sites Sites on the body for measuring temperature include: Mouth (oral): The tip of the thermometer is placed under the tongue and facing toward the back of the mouth. Rectum (rectal): A small amount of petroleum jelly is applied to the end of the thermometer, which is then placed one-half inch inside the anal canal. Rectal thermometers provide the best reading for babies under 3 months. Armpit (axillary): The tip of the thermometer is placed on the skin in the armpit. This measurement method is invariably lower than the rectal or mouth temperature. Ear (tympanic): The top of the ear is pulled back, and an infrared scanning device is gently placed in the ear canal. The device uses heat from the eardrum and surrounding tissue to detect body temperature. Forehead (temporal): An infrared scanning device is slid or aimed across the forehead. It uses heat waves radiating off the forehead (temporal) artery to detect body temperature. What's Considered a Fever? The hypothalamus is a small gland in the brain that controls the body's temperature, like a thermostat. Fever is an increase in body temperature that occurs when the hypothalamus's set point is shifted upwards in response to inflammation or infection. Generally accepted ranges include the following: In healthy babies younger than 3 months, a fever is a rectal temperature of 100.4 F or greater. In children age 3 months to 36 months, a fever is a rectal temperature between 100.4 F and 102.2 F. In older children and adults, a fever is an oral temperature ranging from 100.0 F to 103.0 F. Rectal temperatures should be taken for children under 4 years old, as they provide the most accurate reading. Oral temperatures are generally acceptable for children around 4 or 5 years old. Forehead thermometers may be used for all ages. Axillary and tympanic temperatures are not recommended, as they are unreliable in young children. Low-Grade Fever Temperature Range A low-grade fever generally indicates a body temperature that is slightly above normal. There is no formally defined range, but one research article categorized it as between 99.1 F and 100.4 F. In children, body temperatures between 99.5 F and 101.3 F are considered by some to be elevated. High Fever Temperature Range A high fever indicates a body temperature that is possibly serious or dangerous. Again, there is no formal definition, but typically, a high fever is 102.2 F or greater in babies 3 months and older and younger children. A high fever in older children and adults is a temperature of 102.4 F or greater. Fevers above 105.8 F are termed "hyperpyrexia" and can be seen with brain dysfunction, severe infections, or brain bleeds. An extremely high temperature above 105.8 F sometimes represents hyperthermia, which is different from a fever. Hyperthermia can be rapidly fatal and is caused by a malfunctioning of the body's ability to manage heat coming from the environment. Causes include: How to Break a Fever at Home Many fevers can be safely treated at home with fluids and rest, assuming no symptoms or signs of a serious illness are present. Antipyretic Drugs Sometimes, fever-reducing medicines—called antipyretic agents—are used to ease discomfort, especially if the fever is high or other symptoms related to the fever are present. These can include malaise (general feeling of being unwell), headache, and muscle aches. Antipyretic agents are also often indicated in individuals with underlying heart or lung diseases, as fever can increase heart and breathing rates. Tylenol (acetaminophen) and the nonsteroidal anti-inflammatory drug (NSAID) ibuprofen, sold under the brand names Advil or Motrin, are commonly used antipyretics. Take Precautions Take an antipyretic (or give your child) only under the guidance of a healthcare provider, as they do carry risks. Taking too much Tylenol can cause liver injury and damage. Likewise, too much ibuprofen and other NSAIDs can cause stomach bleeding and may need to be avoided in individuals with heart or kidney disease, high blood pressure (hypertension), or bleeding problems. This is why it is important to read the medication label carefully when giving these medications. Information on the label can help you determine the correct dose and frequency based on your child's weight. Also, the NSAID aspirin should never be used in kids under 19, as it's associated with Reye's syndrome., a life-threatening condition. An antipyretic is often unnecessary in a child older than 3 months who has a rectal temperature less than 102 F (38.9 C), seems well, and is behaving like their usual selves. Cooling Therapies Cooling therapies—such as cooling blankets or cool-water sponge baths—can help reduce fever in adults with high fevers, but only when used concurrently with an antipyretic. This is because physical cooling of the body causes blood vessels in the skin to narrow, decreasing the body's ability to lose heat. Cooling therapies are not recommended in babies or children with a fever-related illness. School and Work With a Fever To prevent the spread of infection, a child or adult should be fever-free for 24 hours without the use of fever-reducing medications) and feel and appear well before returning to school, work, or other activities. Fever Symptoms That Warrant Medical Attention In many instances, seeing a healthcare provider or going to the emergency room is unnecessary for a fever, as the cause is often a viral infection that needs to run its course, typically three to five days. That said, certain factors, such as an ill-appearing child or adult, underlying medical conditions, or worrisome symptoms, warrant medical attention. Babies and Children According to the American Academy of Pediatrics and experts from UpToDate, seek medical attention in the following scenarios: A baby less than 3 months of age with a rectal reading of 100.4 F (38 C) or higher, even if the baby looks well (avoid fever medication until speaking with the healthcare provider) Children age 3 months to 3 years who have had a rectal reading of 100.4 F (38 C) or higher for more than one to three days or who appear ill or are fussy, unusually tired, clingy, or refuse to drink fluids Children aged 3 months to 3 years who have a rectal reading of 102 F (38.9 C) or higher Children of any age whose mouth/ear/rectal/forehead reading is 104 F (40 C) or higher or whose axillary (armpit) reading is 103 F (39.4 C) or higher Children of any age who have a fever and are taking steroids and/or have a chronic medical condition (e.G., cancer or sickle cell disease) Children of any age who have a febrile seizure Children of any age who have been in a sweltering environment, like an overheated car In addition, infants and children with a fever and any of the following symptoms also require immediate medical attention: New skin rash Stiff neck Persistent vomiting or diarrhea Severe headache/sore throat/ear pain Signs of dehydration (e.G., fewer wet diapers, dry mouth, no tears, sunken soft spot). Children of any age with repeating fevers (even if they only last a few hours) without other symptoms for more than seven days or who act or appear ill, even when the fever is reduced, must be seen promptly by a healthcare provider. Adults If you are an adult and have a fever, seek medical attention right away if you: Are pregnant Are recovering from a recent surgery or were recently hospitalized Are taking chemotherapy, steroids, or other drugs that weaken the immune system Think a tick may have bitten you Have a chronic health condition like diabetes, heart disease, or cancer Have recently returned from a trip abroad, namely from Africa, Asia, Latin America, or the Middle East Have fevers that recur or persist Go to your nearest emergency room if your fever is accompanied by one or more of the following symptoms: Skin rash Problems breathing Severe headache or neck pain/stiffness Seizure Feeling confused Severe or persistent vomiting or diarrhea Pain in the stomach, back, or sides Do Not Hesitate to Get Help If you (or your child) have a fever and are experiencing unusual or worrisome symptoms or have that gut instinct that something is wrong, don't hesitate to contact a healthcare provider or go to your nearest emergency room. Causes of Fever There are multiple potential causes of fever. Viral Infections are the most common cause. Examples include: Other causes include bacterial infections such as: Sometimes, fever is caused by a non-infectious condition such as: Autoimmune diseases (e.G., lupus or rheumatoid arthritis) Cancer Reaction to a medication, vaccine, or blood transfusion Acute pancreatitis (inflammation of the pancreas) Acute cholecystitis (inflammation of the gallbladder) Summary Fever is an elevation of the body's temperature and occurs when the set-point of the brain's thermostat shifts upwards. Fever is a response to something in the body, usually a viral infection like the flu or COVID-19. Bacterial infections, such as urinary tract or skin infections, can also trigger fevers, as can noninfectious causes like autoimmune diseases or drug reactions. No formal or standard definition exists for fever, as it can vary depending on age, time of day, and where it's measured on the body (e.G., mouth, rectal, ear, underarm, or forehead). Most cases of fever are due to viral infections. They can be managed at home with fluids, rest, and, sometimes, a fever-reducing medication like Tylenol or ibuprofen (under the guidance of a healthcare provider) That said, certain factors warrant medical attention—for example, a baby less than three months of age with a rectal reading of 100.4 F (38 C) or higher or a young child with a rectal reading of 102 F (38.9 C) or higher. Likewise, the presence of worrisome symptoms, in addition to the fever, like trouble breathing or signs of dehydration, requires immediate medical attention. While many fevers can be managed safely at home, contact a healthcare provider if you have questions or concerns or if your gut instinct is kicking in.

Missouri Teenager Left Paralyzed And On A Ventilator From West Nile Virus

A St. Louis County, Missouri, teenager suffered rare complications from West Nile virus that has left him paralyzed and on a ventilator.

John Procter V said his son's symptoms started around Aug. 8 when he complained of headaches and dizziness.

A doctor told John Procter VI, 18, a recent high school graduate whom the family calls "BB," that he had a tension headache and that he was dehydrated and to get some rest, his father said in an interview Thursday.

The family took him back to the hospital after he started "violently vomiting," his father said. This time, doctors said he had a "stomach bug," gave him over-the-counter medicine and sent him home.

"It didn't get better; it got worse," the older Procter said. "A fever started coming, high fever, 103, 104, could not break them, could not keep anything down, so we took him to a different emergency room. They said he had a stomach bug there, as well. They also thought he had meningitis ... But it came back clear. They sent us home with over-the-counter medicine."

But the teen's symptoms worsened, and he became lethargic, slurred his words and had trouble raising his arms.

"I recognized that he was in some sort of distress, and I believed he was having a stroke," Procter said. "I just picked him up and carried him to the car."

The teen was placed in intensive care at the hospital and diagnosed with West Nile virus, which is commonly spread through infected mosquitoes. There is no vaccine or treatment.

The family said that he is paralyzed from the neck down and that he was placed on a ventilator to help him breathe.

Severe complications from West Nile are rare. About 1 in 150 people experience symptoms that affect the central nervous system, such as inflammation of the brain or meningitis, inflammation of the membranes that surround the brain and the spinal cord, according to the Centers for Disease Control and Prevention. Symptoms of severe illness include neck stiffness, headache, disorientation and paralysis. Recovery can take weeks or months, and some effects can be permanent.

According to the CDC, preliminary data shows at least 18 people have died in the U.S. This year from the virus. Last year, there were 182 deaths.

Erin Staples, a medical epidemiologist with the CDC's Division of Vector-Borne Diseases, urged people to take precautions.

"This is the prime time, the last week of August, the first week of September, when West Nile usually peaks nationally. People need to be using their insect repellent right now," she said.

The Procter family said they hope the teen makes a full recovery. In an update on a GoFundMe page he created, Proctor's father said doctors removed his son's breathing tube "and gave him a [tracheostomy tube] to start breathing rehab and physical therapy."

"Our son is very weak at the moment making small but vast improvements," John Procter V wrote. "His left arm is still very weak, he can't move his neck or sit up [on] his own. Please continue to keep BB lifted up in prayer, pray for our family and his friends during this traumatic time and keep doctors and medical staff elevated in prayer as well."

Dr. Anthony Fauci, the former chief medical adviser to the Biden administration, was recently hospitalized with the virus. He told the health news site STAT that he'd "never been as sick in my life."

"I really felt like I'd been hit by a truck," Fauci, 83, said, adding, "By far, this is the worst I've ever been with an illness." 

Fauci, who was the head of the National Institute of Allergy and Infectious Diseases, said he initially felt like he was coming down with an upper respiratory infection. But he soon began experiencing "shaking chills" and a high fever, and he felt weak. 

He was taken to the hospital on Aug. 16, according to STAT.

Fauci, who is recovering at home, told the news site that the illness left him so weak that he initially couldn't stand without help. 

"I just have to rest," he said. "The good news is I'm absolutely going in the right direction. The sobering news is that it's going to take weeks and weeks to get back to normal. That's the history of West Nile. It just wipes you out so badly." 

10 Mass. Communities Are At High Risk For EEE. Here's What To Know About It.

What is Eastern equine encephalitis?

EEE is a rare but serious disease caused by a virus, the state DPH says on its website.

The disease cycles between mosquito and bird carriers and also affects horses, according to the Centers for Disease Control and Prevention.

"People and other animals, like horses, become infected with the virus when mosquito species that feed on many kinds of animals, feed on infected birds and then bite people," according to the CDC.

How does EEE spread?

Mosquito bites. Symptom onset usually comes "three to ten days" after a bite from an infected mosquito, according to the DPH.

EEE is not contagious among humans, though the CDC says "rare" instances of transmission have been documented in medical transplant procedures.

"Humans and other animals are typically infected by bridge vectors [such as mosquitoes] and are considered dead-end hosts," the CDC says on its website.

Unlike birds, the federal agency says, people and horses "don't develop high levels of virus in their bloodstream and cannot pass the virus on to other biting mosquitoes."

How dangerous is EEE?

The most serious complication associated with the disease is known as encephalitis, or inflammation and swelling of the brain, DPH says. There's no treatment for EEE and about half of the people who contracted it in Massachusetts died from the infection, officials say.

In 2019, 12 people were infected with EEE in Massachusetts and six died. In 2020, there were five human cases in the state and one death, according to state officials. There were no human cases in the state in 2021, 2022, or 2023.

The disease gets progressively worse, officials say, with some patients slipping into a coma within a week.

"People who survive this disease will often be permanently disabled," DPH says. "Few people recover completely."

Who is most at risk?

People over 50, adolescents, and younger children are most at risk from EEE, according to the CDC.

"Persons over 50 years of age and under 15 years of age seem to be at greatest risk for developing severe disease when infected with Eastern equine encephalitis virus," the CDC says.

Earlier this month, the state's first animal case of EEE this year was confirmed in a horse exposed in Plymouth County.

What are the symptoms of EEE?

The DPH says "first symptoms" include fever, often running between 103 and 106 degrees, stiff neck, headache, and lack of energy. Such symptoms "show up three to ten days after a bite from an infected mosquito," the state agency says.

Lahey Hospital & Medical Center in Burlington urged patients to contact their health care providers as soon as they detect symptom onset.

"If you have symptoms of EEE, see your doctor right away," the hospital says on its website. "He or she will take samples of your blood or spinal fluid for testing in the lab. Antibiotics are not effective against EEE or other viral diseases, and no antiviral drugs help with this disease."

How can people protect themselves?

State DPH officials advise the public to avoid scheduling outdoor events from dusk to dawn when mosquitoes are most active.

While outdoors, DPH says, it's best to wear long pants and a long-sleeve shirt and socks, even when the mercury climbs.

"This may be difficult to do when the weather is hot, but it will help keep mosquitoes away from your skin," DPH says.

Residents should also apply repellent containing DEET, picaridin, oil of lemon eucalyptus, or permethrin for shoes and clothes, according to DPH, though some products should not be used on infants and young children.

"DEET products should not be used on infants under two months of age and should be used in concentrations of 30 percent or less on older children," the agency says. "Oil of lemon eucalyptus should not be used on children under 3 years of age. Permethrin products are intended for use on items such as clothing, shoes, bed nets and camping gear and should not be applied to skin."

In addition, people should keep mosquitoes from entering their homes by making sure screens are tightly attached to windows and doors, per DPH. Standing water should be removed.

Are any cities and towns taking action to minimize risk?

Yes. In Plymouth, officials said Friday that they're closing "all parks and fields between the hours of dusk to dawn." Health officials in Oxford are recommending residents stay indoors after 6 p.M. And protect themselves from mosquitoes

Meanwhile, the state's spraying operation is expected to begin Tuesday evening, officials said Monday, with the possibility of additional days of spraying.

"The eight communities in the aerial spray zone are Carver, Halifax, Kingston, Middleborough, Plymouth, Plympton, Rochester, and Wareham," DPH said. "The five communities in the truck spray zone are Douglas, Dudley, Oxford, Sutton, and Uxbridge."

For both aerial and truck-mounted applications, spraying will begin at dusk and continue until approximately 4:30 a.M. The next morning, officials said.

The pesticide being used is Anvil 10+10, which state officials described as "an EPA-registered product extensively tested and used in both ground-level and aerial spraying in the U.S. To control mosquitoes."

Dr. Robbie Goldstein, the DPH commissioner, said in a statement that the current EEE outbreak is the first one to hit Massachusetts in a while.

"We have not seen an outbreak of EEE for four years in Massachusetts," Goldstein said. "This year's outbreak and activity raise the risk for communities in parts of the state. We need to use all our available tools to reduce risk and protect our communities. We are asking everyone to do their part."

His words were echoed by state agricultural resources Commissioner Ashley Randle.

"Due to the increased EEE risk and the first human case of the season, the state is taking decisive action to protect public health," Randle said. "Aerial spraying will target mosquitoes carrying the EEE virus. While these measures are crucial for reducing transmission risk, it's vital for everyone to stay vigilant and follow personal protection guidelines to safeguard our community."

Material from prior Globe stories was used in this report.

Travis Andersen can be reached at travis.Andersen@globe.Com.

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