Norovirus cases are reportedly increasing in several regions across the United States, as indicated by data from the Centers for Disease Control and Prevention (CDC). During the week of December 5, over 90 outbreaks of norovirus were documented, marking a significant rise compared to previous years, where the highest number of outbreaks recorded for the same week was 65.
This national trend is consistent with reports from various states and counties throughout the country. In Minnesota, the Department of Health (MDH) has noted a notable increase in norovirus outbreaks this December, with more than 40 incidents reported—almost double the usual figures for this period.
What is Norovirus?
Norovirus is a highly contagious group of viruses that leads to severe vomiting and diarrhea. It is a prevalent illness, particularly during the colder months when outbreaks are more common. In the United States, norovirus is the leading cause of foodborne illnesses. The first recorded outbreak took place in Norwalk, Ohio, in a school in 1968, which is why the initial strain was named the Norwalk virus.
Norovirus, often referred to as the stomach flu, leads to symptoms such as vomiting, diarrhea, and abdominal cramps. The MDH emphasizes that noroviruses are highly contagious and are the leading cause of foodborne illness outbreaks in the state.
It is estimated that individuals may contract norovirus approximately five times in their lifetime. To mitigate the risk of infection and spread, the MDH advises thorough handwashing with soap and water, as hand sanitizers may not be as effective.
Current News About Norovirus
In December, Minnesota experienced over 40 reported outbreaks, nearly double the typical incidence, as indicated by the state Department of Health. Earlier this month, a gathering honoring premier restaurants in Los Angeles resulted in at least 80 individuals falling ill due to norovirus, which health officials attributed to raw oysters, as confirmed by the county’s Department of Public Health to ABC News.
Norovirus is a highly transmissible pathogen and is recognized as the predominant cause of viral gastroenteritis, characterized by inflammation of the gastrointestinal tract’s inner lining. Commonly referred to as the “stomach bug” or “stomach flu,” norovirus infections are not associated with influenza. According to the Centers for Disease Control and Prevention (CDC), norovirus accounts for 58% of foodborne illnesses in the United States annually.
Norovirus Symptoms
The primary symptoms include nausea, vomiting, abdominal pain, and diarrhea, although patients may also experience fever, headaches, and body aches. The CDC estimates that norovirus leads to 19 to 21 million illnesses, 109,000 hospitalizations, and approximately 900 fatalities each year. Infection can occur through direct contact with an infected individual, sharing food or utensils, touching contaminated surfaces, or consuming tainted food or beverages.
Symptoms typically manifest within 12 to 48 hours post-exposure, but the illness usually resolves swiftly, lasting one to three days in most healthy adults, as per CDC guidelines. There is currently no specific antiviral treatment for norovirus; thus, management focuses on alleviating symptoms.
norovirus treatment
There is no specific antiviral treatment for norovirus; thus, management focuses on alleviating symptoms. The CDC advises maintaining hydration and consuming fluids that restore electrolytes, which may be lost due to vomiting and diarrhea. While most individuals recover within a few days, certain populations, including infants, the elderly, and those with weakened immune systems, are at heightened risk for severe dehydration.
Health professionals emphasize that the most effective preventive measure against norovirus is thorough handwashing with warm, soapy water for at least 20 seconds, as hand sanitizers are less effective against this virus. The CDC recommends handwashing after using the restroom or changing diapers, as well as before eating, preparing, or handling food. To minimize foodborne contamination, it is essential to wash fruits and vegetables thoroughly and ensure that shellfish is cooked to a minimum internal temperature of 145°F.
What distinguishes norovirus from the stomach flu?
Norovirus is responsible for gastroenteritis, often referred to as the “stomach flu,” while the influenza virus is responsible for respiratory flu, not gastroenteritis.
How many types of norovirus are there?
There are multiple strains of norovirus, classified within the Caliciviridae family, which causes inflammation in the stomach and intestines (gastroenteritis). This family includes 10 groups with a total of 48 types, with GII.4 being the most prevalent.
How prevalent is norovirus?
Norovirus is extremely common, with approximately 685 million cases reported worldwide each year. Out of these, over 200 million cases involve children.
Is norovirus seasonal?
Norovirus outbreaks typically occur from November to April in regions north of the equator and from April to September in areas south of the equator. In equatorial regions, outbreaks do not follow a specific seasonal pattern.
What are the risk factors associated with norovirus?
Norovirus can affect anyone. However, your chances of contracting norovirus increase if you:
- Have close contact with an infected individual.
- Possess genetic traits that make you more prone to experiencing symptoms.
What complications can arise from norovirus?
Experiencing norovirus can lead to significant illness, resulting in vomiting and diarrhea. This can hinder your body’s ability to retain nutrients, putting you at risk for dehydration. Signs of dehydration include:
- Reduced urination or dark urine.
- A dry mouth.
- Weakness or dizziness.
- Headaches.
In children, additional symptoms may include:
- Crying without producing tears.
- Increased irritability.
- Excessive sleepiness during the day.
Norovirus can hinder your ability to eat or drink due to inflammation in the stomach and intestines, leading to vomiting or diarrhea. It is important to continue trying to eat and drink. You can manage this by consuming smaller amounts more frequently, eating slowly, and taking small sips of fluids. Eating too quickly or in large quantities may cause your body to reject the food.
Norovirus prevention strategies
Norovirus prevention strategies are essential for reducing the likelihood of infection. Key measures include:
- Regularly washing hands with soap and water.
- Thoroughly rinsing fruits and vegetables prior to consumption.
- Cooking food adequately, particularly seafood and shellfish, to a minimum internal temperature of 145 degrees Fahrenheit (62.77 degrees Celsius).
- Avoiding close contact with individuals who are infected with norovirus.
- Regularly cleaning and disinfecting frequently touched surfaces and items.
- Washing clothing thoroughly, especially if contaminated.
It is important to note that hand sanitizers are less effective against norovirus than washing hands with soap and warm water. Individuals infected with norovirus should refrain from preparing food or caring for others to prevent further transmission of the virus.
Regarding susceptibility, it is indeed possible to contract norovirus multiple times. This is due to the existence of various strains of the virus. While the body may develop some immunity to the initial strain, this protection does not extend to all variants. Consequently, individuals may experience recurrent norovirus infections throughout their lives, and any immunity developed may diminish over time, leading to potential gaps between infections.
