The second time I had a scare about bed bugs, my landlord said he thought I might be overreacting a bit. My husband and I had fought off an infestation just five months earlier. Now, after finding one bed bug on my pillow (which was probably sitting there due to bites), I was looking for a response from the building. “You know they don’t cause disease,” the landlord told me.
common sense As my landlord said, he doesn’t think bed bugs can spread disease to humans. Or at least, since these insects are so widespread and frequently sting humans, we would be aware if they were carrying dangerous diseases. Most other blood-sucking insects that regularly bite humans, such as mosquitoes and ticks, transmit deadly human pathogens. But recent research suggests that bed bugs may be able to transmit human disease after all, even if they’re not already silently transmitting it.
Proving that bed bugs transmit human disease means proving three important things. One is that those microorganisms can survive and thrive inside the bed bug’s body. And recent research has proven that bed bugs naturally store a lot of stuff. of the virus. The genetic material of some human pathogens— Among them is MRSA, bartonella quintana, and Hepatitis C—was also found For bed bugs outside the lab.
The second criterion is that bed bugs can transmit pathogens. in laboratory research Jose Pietri, an associate professor of entomology at Purdue University, and his colleagues showed in a paper published in January that bed bugs can become infected and transmit MRSA while feeding. (They used membranes contaminated with MRSA instead of human skin.) A 2014 study showed that bed bugs can spread the pathogen that causes Chagas disease to mice.
And third, the missing piece: infection must occur in the natural environment, not just in the laboratory. “There may be some variables that we don’t understand” that are preventing bed bug disease transmission from being detected, Pietri told me. “Or maybe it’s just not that common.”
Pietri, like several scientists I spoke with, was drawn to studying bed bugs’ potential for disease transmission. Because existing research was not conclusive for him. Scientists first confirmed that insects could carry diseases in the late 19th century, and in the decades that followed, researchers tried to identify whether bed bugs were also dangerous. They tried to infect bed bugs with microorganisms. They crushed up bed bugs and injected them under the monkey’s skin. They investigated whether sexually transmitted diseases could breed in insects taken from brothels in West Africa. There have been no experiments directly linking bed bugs to human disease.
There was no real evidence that the human disease was transmitted, and there were enough failures to establish a link in the lab that many researchers ultimately concluded that, at least in this respect, bed bugs are harmless. I attached it. A 2012 paper states: “More than 200 million bed bug bites (and multiple bites), with no evidence of any disease occurring as a result, suggests that the risk of contracting an infectious disease from a bed bug bite is very high. . Almost non-existent.”
For Pietri, who studies urban pests and vector-borne diseases, all this evidence is not only inconclusive, but outdated. Bed bugs have many close relatives that carry disease, so why? do not have bed bugs? ““I don’t think it’s a solid scientific argument to say that because we don’t see this phenomenon, it won’t happen,” he told me. “That’s an incomplete picture.”
About 15 years ago, bed bugs Reinvade cities around the world, including New Yorkdisappeared for decades due to DDT and other pesticides. As bed bug panic grows, Pietri isn’t the only scientist to wonder whether bed bugs’ ability to transmit disease is understudied. Michael Levy, a professor of epidemiology at the University of Pennsylvania who led the 2014 study, said the lab that demonstrated the potential of bed bugs as a vector for Chagas disease was inspired by a paragraph-long description of a 1912 study. That’s what it means. Confirming results from 100 years ago, the research team found that insect faeces can transmit the disease through the skin of mice punctured by stings or bites. Investigating this problem has become much easier thanks to techniques such as genetic sequencing that allow researchers to more easily identify microbes within insects. Only in the last five years have researchers been able to comprehensively examine the viruses and bacteria that bed bugs can carry, Pietri said.
None of the researchers I spoke to believe that bed bugs are as likely to be a harmful vector as mosquitoes. First, bed bugs cannot fly and are poor walkers, so they must hitchhike to travel significant distances. Therefore, they are less likely to spread the disease widely. “Given the biology of bed bugs, they are unlikely to transmit disease,” Koby Schall, an entomologist at North Carolina State University, told me. “But can we do that? Probably so.” However, more serious infections can occur in certain locations, such as hospitals and shelters, where infection rates are high and bed turnover is high. Pietri thinks researchers may simply not be looking for the right places for bedbugs to carry human diseases. bartonellaBed bugs, a bacteria transmitted by fleas and body bugs in general, are particularly common among people experiencing homelessness, for example, but research on bed bugs in temporarily homeless populations is almost never done. Levy said she also worries that bed bugs can spread diseases such as Chagas among people sleeping in the same bed in the house.
The bed bug research community is small, and some adhere to the old wisdom that bed bugs are unlikely to spread disease. Google bed bugsvisit the CDC website, or talk to your friendly local exterminator and you’ll see that’s the consensus. And if bedbugs don’t transmit disease, that could also provide important insights. One hypothesis is that bed bugs’ immune systems may have evolved to be particularly robust due to their brutal mating rituals, which expose them to daily microbial invasion. Understanding the mechanisms that prevent infection could help fight infections caused by other insect vectors, such as mosquitoes, for example, Pietri said.
If researchers prove a link between bed bugs and human disease, it would add a new dimension to the already serious suffering that bed bugs inflict on their hosts. At the same time, the discovery could help attract more funding toward understanding pests that are widely considered to pose less of a threat to public health than those that clearly spread disease, Levy said. he told me. (In his experience, the only government agency interested in funding bed bug research was the National Institutes of Health Sleep Center.) Bed bug numbers and their ability to evade treatment continue to increase. Increasing knowledge about bed bugs may be particularly important during this time. They have brought into my own life insomnia, paranoia, and the most itchy, persistent bites I have ever experienced. Whether they spread disease or not, bed bugs are certainly not harmless.
