Norovirus – the bug that causes stomach flu – is associated with contaminated water and contaminated fresh produce, and is often traced to the surface of the produce. But until recently, it was unclear how fruit and vegetables became contaminated with the virus. A recent study has discovered that that many growers dilute their pesticides with water contaminated with norovirus, suggesting that the application of pesticides not only poses a chemical health risk, but can also pose a microbiological health risk.

Where Norovirus Can Be Found

The Human Norovirus (HNoV) is often found in surface water (lakes, rivers, etc.) and well water – water sources used by many growers on their crops directly and through reconstituted pesticide use. Currently there is no cure for this notorious stomach bug. The only recourse for those infected is to let their body flush out the virus naturally and let the stomach flu run its course. This means enduring vomiting, stomach pain, and diarrhea for a few days, or even up to a week.

The study, published in the Journal of Food Microbiology, tested the theory of contaminated water from various sources being the point of origin of the virus. Farmers often use these different water sources to dilute their pesticides and in the study, it was found that 1) water samples collected from these sources were often contaminated with HNoV, and 2) the pesticides diluted with these contaminated water samples do not counteract the infectivity of the virus.

How to Prevent Infection

If the strong chemicals in pesticides cannot kill human norovirus, how can people protect themselves against infection? As with all diseases, prevention is always better than cure. If a little care and time is spent on ensuring water safety, millions of people can avoid contracting stomach flu.

The Centers for Disease Control and Prevention (CDC) suggest a few simple ways to lessen the chance of contracting and spreading HNoV:

1. Bleaching – This is the use of a water-and-bleach solution, at a concentration of 5.25% per gallon of water, to clean different non-porous surfaces at home. 2. Boiling – To prevent infection, both tap water and water that is collected from natural sources, which is used for consumption should be boiled to kill any viruses present. Alternatively, use a good quality water filter like a Berkey water filter that is capable of removing any viruses that may be lurking in the water. 3. Hand washing – This is the simplest way to prevent infection. Everyone should develop the habit of properly and regularly washing their hands. 4. Wash fruit and vegetables – wash fresh fruit and veggies thoroughly, or peel before consuming. 5. Eating Organic Food – Nutritionists recommend eating more naturally grown food to avoid the health risks associated with pesticide use.

Decontamination of water by boiling or bleaching may involve a little more work for farmers, but the benefits outweigh the health risks in not taking any measures at all. For small scale operators, a simpler option may be to filter the water before using it to dilute pesticides.

HNoV is a highly contagious virus and one of the most common viruses in the world, according to the Center for Infectious Disease Control in the Netherlands. In the United States alone, the virus infects 23 million people and causes 800 deaths every year. In developing countries, approximately 200,000 children under five years contract human norovirus every year. Yet, by taking simple measures to remove or kill any viruses that may be present in water, unnecessary illness can be prevented.