[Public Health] Protectors of Public Health

According to the Centers for Disease Control and Prevention (CDC), the World Health Organization and other groups, structural pests can cause disease and commonly carry pathogens that can infect people with diseases. Of course, not all pest-related diseases are caused by pests exclusively. Environmental conditions, interaction with pests and control measures may contribute to chances of disease transmission.

In many parts of the world, pest-borne diseases cause many fatalities. We are fortunate that in the United States, pest-borne diseases are notable, but not a major concern. However, to keep the disease in perspective, more than a million people die of malaria each year, according to the CDC. Malaria deaths worldwide cause more than twice the number of cancer deaths in the United States.

Disease related to pests in our industry is significant. The following diseases — and their affiliated pests — are a few examples of how our industry can help protect the health of the general population.

SALMONELLOSIS. One of the greatest fears of any quality assurance manager in a food plant or restaurant manager is an outbreak of Salmonella. Salmonella spp. can be associated with many food-borne illness outbreaks. The U.S. Food and Drug Administration (FDA) estimates that there are up to 4 million cases of this disease each year. From an infective dose of as low as 20 cells, this disease causes vomiting and diarrhea several days after a critical exposure. This disease is treatable with antibiotics, but can be fatal to immunocompromised individuals or the young or the infirm. While this disease traditionally is associated with dairy products, undercooked poultry and poultry products, or exposure to affected humans, it can be transmitted by pets, cattle or even reptiles.

Cockroaches, stored product pests and rodents can transmit the disease by moving from an infected area to an area where humans are exposed. Certainly, not all cases related to salmonellosis are caused by pests, but pests can transmit the disease from contaminated food to uncontaminated food.

Pest management professionals can reduce chances of Salmonella infection by managing roaches, rodents and stored product pests in commercial and residential accounts.

LYME DISEASE. Not long ago, Lyme disease was not even identified as a specific disease, but today it is feared by parents as a disease that threatens their children. Lyme is caused by the bacterium Borrelia burgdorferi and is transmitted by infected blacklegged ticks. These ticks are found in exterior areas and may be found near homes, schools and ball fields.

While the greatest concentration of Lyme disease was reported in the East and the upper Midwest, the disease has reached nearly every state. Symptoms include general lethargy and aching joints, symptoms typically reported for many illnesses. So, misdiagnosis of Lyme disease is assumed and there may be more cases than diagnosed. Lyme is treatable with antibiotics. Proper tick management is the key to preventing Lyme disease. One method is landscape modification, so that exterior areas are less hospitable to ticks. Also, parents are now informed about how to look for ticks on their children.

HISTOPLASMOSIS. Histoplasmosis is caused by the fungus Histoplasma capsulatum. This fungus will grow in soil contaminated with bat or bird droppings, and is treatable. Symptoms include fever, chest pains and dry cough — again, symptoms that may be diagnosed as something other than the root disease.

The disease may spread to the respiratory system and at that point, may be fatal. Chronic effects may be similar to tuberculosis.

The fungus typically is found in bird roosting areas, poultry rearing areas and in areas infested with bats. Any person may become infected and untrained people should avoid areas where there is an abundance of bird or bat droppings. Technicians should wear proper respiratory protection when working in areas with heavy bird or bat droppings.

LYMPHOCYTIC CHORIOMENINGITIS. The house mouse is a common reservoir for lymphocytic choriomeningitis. Many home-owners have yet to understand the potential health consequences of allowing house mice to infest structures. The infectious agent in this case is the lymphocytic choriomeningitis virus and is transmitted by the droppings, saliva and urine of infected animals. This disease may be spread by breathing in infected areas, or by handling mouse droppings with an open cut. Other animals also may transmit the disease. Similar to hantavirus, prevention of this disease requires the use of personal protective equipment if there is a suspicion of heavy activity. Forthcoming research, sponsored by NPMA’s Pest Management Foundation, will allow us to have a better understanding as to incidence of lymphocytic choriomeningitis.

Symptoms are flu-like with headache and lethargy followed by recovery. It is interesting that so many diseases are flu-like and it makes one wonder as to how many pest-borne diseases are undiagnosed when a medical professional diagnoses flu-like symptoms as “just the flu.”

CONCLUSION. Today, we discuss pests as disease vectors more than ever in recent years. Other diseases such as West Nile virus, encephalitis, hantavirus, ehrlichiosis and others continue to plague North America. We are indeed very fortunate in North America in that fatality rate due to pests is minimal compared to other parts of the world; however, these diseases show the continuing importance of professional pest management.

The author is vice president, technical services, of the National Pest Management Association.