Drinking blood exposes people to rare TB strain

Cultural practices that involve eating undercooked meat or drinking blood or unsterilised milk are placing people at risk of contracting a rare strain of tuberculosis.

In Maasai culture “it is so normal for us to take milk that is not boiled, drink blood straight from the cow or goat when they’re being slaughtered plus eating meat that it not well done,” Timpiyian Leseni told Health-e News.

'I used to drink blood a lot'

Although she didn’t know it at the time, these actions were exposing her to a lesser-known strain of tuberculosis (TB).

“As a Maasai woman I used to drink blood a lot,” she said from her home in Kenya. “I believe this is how I got zoonotic TB.”

According to the International Union Against Tuberculosis and Lung Disease, while conventional TB is caused by the bacterium Mycobacterium tuberculosis, zoonotic TB is caused by Mycobacterium bovis. It is transmitted from animals to humans primarily though unpasteurised dairy products and sometimes through eating infected under-cooked meat. It can also be transmitted from humans to other humans.

Leseni suffered. She was misdiagnosed because of the lack of awareness of this form of the disease and underwent two unnecessary operations.

Countries across Africa and some in Asia are worst hit, according to the Union’s Professor Simeon Cadmus, a zoonotic TB specialist, who said that many of these countries lack the infrastructure and capacity to correctly diagnose and treat zoonotic TB – including in his home country of Nigeria.

Significantly underdiagnosed

The strain is naturally resistant to one of the most common anti-TB drugs and patients need to be treated with a non-standard regimen for a chance of cure.

But many patients are missed because people “simply don’t look for it”, said scientific director for the Union Dr Paula Fujiwara.

She said that only 2% of global TB cases are caused by zoonotic TB but it is neglected: it is significantly under-diagnosed, especially in countries where it is most prevalent.

She said that although this number might seem low, if the world wants to meet the international goal passed by the World Health Assembly to effectively end TB as a public health threat by 2030, we cannot ignore zoonotic TB.

In collaboration with the World Health Organisation, the World Organisation for Animal Health, and the United Nations’ Food and Agricultural Organisation, the Union launched the first ever Roadmap for Zoonotic TB.

Routine pasteurisation needed

Countries where cattle are controlled and food safety standards are high do not have much risk but the document, which was launched at the Union World Conference on Lung Health taking place in Mexico, outlines 10 priorities for countries where this is not the case.

These include improved data collection and research to assess the true scale of the problem, improved diagnosis and awareness of zoonotic TB. It also advocates for the routine pasteurisation of dairy products and for ensuring animal health.

In South Africa, there have been multiple reports of TB in wildlife and even of transmission of zoonotic TB from a wildebeest to a veterinarian working in a private game reserve, but cases among the general population are rare, according to the Department of Health’s Dr Norbert Njeka, head of drug-resistant TB.

However, zoonotic TB cases are not routinely reported by the department and, said Njeka, it is not on the country’s public health agenda just yet.

Wrong diagnoses

But Leseni said that her experience shows that more global attention is needed on the issue.

“There is need for clinicians to be trained on zoonotic TB because I underwent two operations because of negligence,” she said.

The doctors who removed tissue from her abdomen during her first operation did not send it for diagnostic tests and she was instead treated with regular antibiotics “making my situation worsen and leading to the second operation which was major”.

“This means we may be losing a lot of patients who are dying of zoonotic TB because of wrong diagnoses and yet it is a disease that is preventable, curable and treatable.” – Health- e News.

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