Tag Archives: hantavirus

Mono County Issues Hantavirus Warning

May 14, 2020 – As the weather is warming and people are spring cleaning, Mono County Health Department would like to remind residents of the risk of hantavirus in the Eastern Sierra, a known region of exposure in the United States.

People may catch hantavirus by inhaling virus that is found in the urine, feces, saliva, and nesting materials of infected deer mice. Most people who become ill with hantavirus report some exposure to rodents in the preceding weeks, typically while cleaning enclosed spaces that have been closed-up for some time with mice living there.

For more information on hantavirus, click here.

Hantavirus illness begins with a fever and flu-like symptoms, such as headache and body aches, typically one to five weeks after inhaling the virus. Gastrointestinal symptoms such as vomiting, diarrhea and abdominal pain are common in the early part of the illness. Respiratory symptoms, including cough and feeling short of breath, may develop after a few days, signaling increased chance of deadly respiratory and heart failure. When people start having trouble breathing, their condition may rapidly worsen and become critical. There is no specific treatment for hantavirus infection, but high-level intensive care has allowed many people with life-threatening illness to survive. Overall, approximately 25-33% people with hantavirus infection die.

It is important to note key similarities and differences between hantavirus infection and COVID-19. For one, COVID-19 is spread from person to person, whereas hantavirus is spread from deer mouse waste. A person with hantavirus cannot spread it to another person. Both infections may present with flu like symptoms such as fever, fatigue, cough, shortness of breath, or muscle pains. This is why it is critical for residents to be aware of and avoid exposure to rodents, their waste, and their nesting materials. If you begin experiencing any of these symptoms, you should call your primary healthcare provider or the Mono County Nurse Hotline at 211. Be sure to inform health professionals of any exposures you may have had to both mouse waste and COVID-19. Timely hantavirus and COVID-19 diagnosis and potential transfer to higher level hospital care is crucial as these diseases can progress rapidly.

To decrease risk of hantavirus infection:

• Open windows and doors of a potentially contaminated area and allow it to air out for at least 30 minutes before cleaning. Cross-ventilation is best.

• Avoid sweeping, vacuuming or other activities that stir up dust and dirt that may contain the virus.

• Spray dead rodents, nests, droppings, and other potentially contaminated items and surfaces with a 10% bleach solution (1 part bleach with 10 parts water) or a disinfectant made to kill viruses (check the label). A dead mouse caught in a trap should not be removed from the trap. Instead, the trap and mouse together should be disinfected, bagged and discarded into the trash.

• Wait at least 5 minutes after spraying the disinfectant on things before wiping.

• Inspect vehicles for rodents. Mice incursion in vehicles may also pose some hantavirus risk, especially if mice infest the heating and air conditioning system.

• Minimize mouse entry points at home and at work. Mice may enter through very small gaps under doors or around windows and where conduits and vents pass through walls. Heating and air conditions ducts should be periodically inspected for holes and/or rodent feces or nesting material.

Eastern Sierra Resident Dies From Hantavirus

In late November, a resident living in Mono County died of a hantavirus infection. This is the first death that is a result of hantavirus in California this year, and the third confirmed case in Mono County in 2019.

The victim of the virus received treatment in Reno, Nevada where the individual succumbed to the viral strand of hantavirus known as sin nombre. According to medical research website, UpToDate, there are eleven pathogenic species that have been identified throughout the world, and they differ depending on which species of rodent is infected.

In this case, the sin nombre strand is common among deer mice, a wide spread rodent in both Inyo and Mono Counties. Dr. Tom Boo, the Mono County Public Health Officer said, “In Mono County, about 25% of all deer mice carry sin nombre, which is significantly higher than the average rate in the state.”

After it was determined that the Mono County resident died as a result of hantavirus, both state and county health department experts investigated the individual’s residence and place of employment, evidence was found that suggested mice were in and around the home. As for the victim’s place of work which is a school in Inyo County, investigators determined exposure at the location to be “unlikely because minimal signs of mice were found.” according to an official press release from the Mono County Health Department and Inyo County Health and Human Services Department.

According to the California Department of Public Health’s hantavirus statistical data base, there have been eighteen cases between 1980-2017, which is higher than all other fifty-seven counties in the state. In an email interview with KIBS, CDPH discussed why they believe there are more incidents in Mono County. “The rural nature of Mono County may contribute to the high number of human cases detected from that county.” the state agency said.

Elevation is another factor that comes into play when discussing hantavirus. The higher the altitude, the higher the chance deer mice carry the disease. “Elevation may play a role in the number of infected deer mice.” the department wrote. “From disease monitoring data collected by CDPH throughout California over many years, we have observed that the percentage of deer mice with antibodies to SNV [sin nombre virus] increases with increasing elevation. For example, the percentage of SNV-antibody positive deer mice may be less than 10% at sea level and as high as 35% above 10,000 feet elevation.”

The sin nombre pathogen of hantavirus can present itself in a number of ways. Transmission of the virus comes after an individual breathes in contaminated air usually found in an enclosed space. “About 1-5 weeks after exposure, symptoms develop. Early symptoms of hantavirus pulmonary syndrome (HPS) include fever, headache, and muscle aches. Other possible early symptoms include dizziness, chills, vomiting, diarrhea, and abdominal pain.” the CDPH said.

When these symptoms are identified, respiratory problems develop, which can lead to death. “After 2 to 7 days of these symptoms, patients develop breathing difficulties that range from cough and shortness of breath to severe respiratory failure. Approximately 36 percent of HPS patients die from the disease.”

The hantavirus has no cure, but there are steps that can be taken to prevent contraction of the virus. Exposure to the virus is typically in enclosed spaces and occurs when cleaning out small, confined deer mice-infested spaces where there is little air circulation, so it is important to allow air flow into a potentially contaminated area. “Before entering an enclosed area that may be infested with rodents, allow it to air out for at least 30 minutes. Also, avoid contact with all wild rodents, their droppings, and nesting materials.” The Department of Public Health said.

Edit: The article stated that the resident lived in Chalfant, CA. The article has been edited as the Mono County Department of Public Health say the information reported was inaccurate.

LOCAL FLU ACTIVITY

Health Officer warns that flu season is not quite over

Posted by Seth Conners

According to County Health officer Richard Johnson, levels of flu-like activity continues to decrease both nationally and statewide, but the levels in Mono County, as measured by activity in the Sierra Park Clinics, continue above expected levels for this time of year (as of Saturday April 1st – not an April Fool’s joke!)

While the 2016-2017 influenza season has peaked, flu activity (https://www.cdc.gov/flu/weekly/index.htm) is still elevated in the U.S. and is expected to continue for several weeks.
We recommend a yearly fly vaccine (https://www.cdc.gov/flu/protect/keyfacts.htm) for everyone 6 months and older. This season’s flu vaccines (https://www.cdc.gov/flu/spotlights/flu-vaccine-reducing-risk.htm) are reducing risk of illness by nearly half.
Of note – there have been 61 influenza-associated deaths in children so far this flu season, and most of the deaths have been in unvaccinated kids. We routinely recommend that influenza vaccination continue as long as flu viruses are circulating.
We also recommend prompt treatment with influenza anti-viral drugs (https://www.cdc.gov/flu/antivirals/whatyoushould.htm) for people who are very sick with flu and people who are at high risk of flu complications who get flu.
Therefore, all current policies and orders remain in effect:

1. The masking requirement for healthcare workers who have not received this year’s seasonal influenza vaccine continues. We will re-evaluate this requirement at the beginning of each week.

2. All persons entering a healthcare facility with a cough should wear a mask, and be placed into a private exam room as soon as possible.

3. Staff should stay home if they are sick!

4. All persons with a respiratory illness should:
– cover their cough/sneeze
– wash hands frequently
– stay home from work or school
– seek medical advice early for the very young (less than 6 months of age), have chronic medical conditions, of are >65 years of age.
– begin to have trouble breathing, cannot keep fluids down and stay hydrated, or have fever lasting longer than 3-5 days

In addition, as we enter the season when flu is declining, and people begin spring activities, remember that a severe flu-like illness could be caused by the hantavirus!

Hanta Virus update

Health officer rumor control

Inyo and Mono county public heath officer Dr. Richard Johnson is dispelling rumors of a virus circulating in the community of Mammoth.  According to Dr. Johnson there is a unconfirmed rumor that is being circulated that there is “a nasty virus circulating that is killing people in town”. In response, at least one residence has been “tented” to eliminate this risk. Dr. Johnson is presuming – perhaps incorrectly – that the alleged culprit is the hantavirus.

According to Dr. Johnson, “First, there is no nasty virus killing people in town, that I am aware of – hantavirus, or otherwise. We have not had a case of hantavirus this year in the Eastern Sierra, although there have been at least 3 deaths in Colorado so far. We also have not had any unexplained deaths due to a “nasty virus”.

Johnson goes on to say, “Second, ‘tenting’ as one would do for termites, is not an appropriate response to the threat from hantavirus. If you create a void by killing off mice, more will move in to fill the void. Third, yes, we live in an area where we all are always at risk for exposure to the hantavirus. The drought is forcing all animals, including mice, into the human interface where we have chosen to live and visit, in their search for food for survival. So, don’t let down your guard. Do the right thing!”

Although mice carry the hantavirus all year, this is the start of the season when humans typically begin activities that put them at risk of being exposed to the hantavirus. Spring cleaning activities, such as opening up closed buildings that have been unused overwinter, often provide habitats for deer mice and become sites for human exposure to the hantavirus. Although hantavirus infections are relatively rare, it is not unusual for us to have several cases per year in the Eastern Sierra. The risk of death is significant. Individuals cleaning areas where the mice may be present are well advised to heed the recommendations below in order to avoid exposure.

Hantavirus is carried by certain species of rats and mice, and especially the deer mouse, pictured above. Infected rodents shed the virus in their urine, droppings, and saliva. The virus can be transmitted to people when infected mouse urine, saliva, droppings, or nesting materials are stirred
up, temporarily aerosolizing the virus, which can be breathed in by humans.

Inyo/Mono public health recommends the following precautions:

  • seal openings that may allow mice to enter homes and workplaces;
  • remove brush, woodpiles, trash, and other items that may attract mice;
  • tightly close garbage cans, pet food containers, and other food
    sources;
  • wear protective gloves to handle dead mice or to clean up nesting areas, urine, or droppings;
  • before cleaning up nests or droppings found inside, open windows and doors to ventilate the area for at least 30 minutes;
  • do not stir up nests by sweeping or vacuuming. Dampen areas before clean-up;
  • use a disinfectant or 1-to-10 bleach-water mixture to clean up dead rodents, nests, urine, and droppings.

Early symptoms of hantavirus infection include fatigue, fever, and muscle aches. These symptoms may be accompanied by headaches, dizziness, chills, nausea, vomiting, diarrhea, and abdominal pain. Later symptoms include coughing and shortness of breath. If hantavirus is suspected, people should contact their health care provider immediately. Remember, infections with hantavirus may feel like the “flu”; however, it is no longer flu season!

dr richard johnson, hantavirus, eastern sierra news, mammoth lake california