Thursday, April 11, 2019

Antimicrobial Resistance and PrEP: Medical Disasters

Here are two antimicrobial resistance (AMR) scenarios, one rapidly spiraling out of control, and the other (arguably) incipient:

The AMR scenario that is spiraling out of control is described in an article in The New York Times. The development of AMR is blamed on overuse and misuse of cheap antibiotics, usually without prescription. Ever-increasing use and misuse of antibiotics results in ever-increasing development of resistant strains of pathogens.

The NYT article describes the appalling conditions that an estimated one billion people live in; slums where waterborne, foodborne and airborne pathogens thrive. Unable to escape the risks, people try to treat the symptoms with antibiotics, inevitably leading to resistance to most or all available treatments.

The scenario described is a loop: widespread disease leads to overuse of antimicrobials; this leads to development of resistance; people with resistant conditions, if they survive, are taken to healthcare facilities, which also overuse antimicrobials, amplifying resistance and transmission of resistant strains; this loops back to the slum, resulting in an even higher disease burden, and greater levels of resistance.

The loop could be broken by: 1) improving the environment, including water, sanitation, habitation, food, etc and 2) improving conditions in healthcare facilities, infection control, safety, hygiene, etc. This will reduce antimicrobial use and, therefore, resistance.

The approach suggested by the Global AMR R&D Hub, on the other hand, risks speeding up the loop leading to AMR. They aim to “tackle the threat of resistant pathogens” by developing “new antibiotics and treatments against infections.” Producing antimicrobials of ever-increasing power, without addressing 1 and 2, above, only continues the cycle of ever-increasing resistance.

The other scenario is described on websites such as (and and others). They advise on the use of PrEP (pre-exposure prophylaxis), antiretrovirals taken by HIV negative people to reduce the risk of HIV infection. For example, if "you have sex in a variety of situations where condoms are not easily used or not always used", PrEP, if properly used, can reduce risk of infection with HIV by more than 90%.

There are (at least) two problems with this. Firstly, overuse or incorrect use of antiretrovirals can give rise to a resistant strain of HIV developing in an infected person, and that resistant strain can also be transmitted to others.

Secondly, the advice from (and other similar sites, such as is aimed at people who frequently have sex without protection from other sexually transmitted infections (STIs). Exposing yourself repeatedly to infection with STIs increases the development of resistant strains of, for example, gonorrhea, shigella and Mycoplasma genitalium.

Use of PrEP without condoms also increases transmission of hepatitis C virus: “Incidence of acute hepatitis C virus (HCV) among men who have sex with men who use PrEP in Lyon increased tenfold between 2016 and 2017”. HCV has doubled among HIV positive people.

The Center for Strategic and International Studies spectacularly fail to notice the positive feedback mechanism, whereby improper use of PrEP could increase transmission of STIs and the development of resistance in countries where HIV prevalence is highest, sub-Saharan African countries:

"In areas where there is so much HIV circulating, every sexual encounter is high risk, and widespread PrEP could be a prevention lynchpin." The same article even acknowledges that "High rates of sexually transmitted infections (STIs) increase the risk of HIV acquisition", without noticing how PrEP will increase STIs and resistance!

According to The WHO, health is a "State of complete physical, mental, and social well being, and not merely the absence of disease or infirmity." In the two AMR scenarios described above, producing stronger antimicrobials and PrEP are examples of medicalization of health, viewing it as merely the absence of disease or infirmity. These kinds of medicalization will radically increase AMR.


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