Why HIV, malaria, TB are ‘untreatable,’ by WHO

*‘Proposed cuts in U.S. funding to Nigeria, 18 others will cause 67m more cases, 290,649 deaths in four years’
The World Health Organisation (WHO) has raised fresh alarm that malaria, Human Immuno-deficiency Virus (HIV) and tuberculosis (TB) may become untreatable soon.

According to the WHO, globally, 480 000 people develop multi-drug resistant TB each year, and drug resistance is starting to complicate the fight against HIV and malaria, as well.

Antimicrobial resistance (AMR) happens when microorganisms (such as bacteria, fungi, viruses, and parasites) change when they are exposed to antimicrobial drugs (such as antibiotics, antifungals, antivirals, antimalarials, and anthelmintics). Microorganisms that develop antimicrobial resistance are sometimes referred to as “superbugs”.

Also, a mathematical model published this week in the journal PLOS Medicine has shown that cutting the budget of the United States (U.S.) President’s Malaria Initiative (PMI) by 44 per cent, as the U.S. Congress has proposed, would lead to an estimated 67 million additional cases of malaria over the next four years.

Peter Winskill and his team of researchers at Imperial College London, United Kingdom (U.K.) conducted the study.

The PMI, established in 2005 and funded by the US Agency for International Development (USAID), has provided ongoing support to malaria control programmes in 19 African countries including Nigeria and is the largest bilateral funder of malaria prevention and treatment. In May 2017, Congress published a budget justification document, which included a 44 per cent proposed reduction to PMI funding for 2018. In the new study, the researchers inputted data on PMI funding and epidemiology into an established model of Plasmodium falciparum malaria to project the impact of reductions in funding.

Until now, Nigeria and most other developing nations depend over 75 per cent on funds from PMI and the Global Funds for AIDS, TB and Malaria for their control programmes.

According to the study, if funding is maintained, PMI-funded interventions are estimated to avert 162 million more cases of malaria and save 692,589 lives between 2017 and 2020 compared to no PMI support. If a 44 per cent reduction in funding occurs, the model revealed that this loss of direct aid could result in an additional 67 million cases of malaria and 290,649 deaths between 2017 and 2020 compared to maintaining current levels of funding.

The authors said: “Our results provide a conservative estimate of the overall impact of PMI funding as we do not capture the impact of all PMI-associated activities. PMI’s ongoing support… in counties of high burden or strategic importance is vital in order to avoid a rapid erosion of the progress made in the last 15 years on the road towards malaria eradication.”

The other researchers include: Hannah C. Slater, Jamie T. Griffin, Azra C. Ghani, and Patrick G. T. Walker.

The study is titled “The US President’s Malaria Initiative, Plasmodium falciparum transmission and mortality: A modelling study.”

Meanwhile, WHO estimates that, in 2014, there were about 480 000 new cases of multidrug-resistant tuberculosis (MDR-TB), a form of tuberculosis that is resistant to the two most powerful anti-TB drugs. Only about a quarter of these (123 000 cases) were detected and reported. MDR-TB requires treatment courses that are much longer and less effective than those for non-resistant TB. Globally, only half of MDR-TB patients were successfully treated in 2014.

Among new TB cases in 2014, an estimated 3.3 per cent were multidrug-resistant. The proportion is higher among people previously treated for TB, at 20 per cent.

Extensively drug-resistant tuberculosis (XDR-TB), a form of tuberculosis that is resistant to at least four of the core anti-TB drugs, has been identified in 105 countries. An estimated 9.7 per cent of people with MDR-TB have XDR-TB.

According to the WHO, as of July 2016, resistance to the first-line treatment for P. falciparum malaria (artemisinin-based combination therapies, also known as ACTs) has been confirmed in five countries of the Greater Mekong subregion (Cambodia, the Lao People’s Democratic Republic, Myanmar, Thailand and Viet Nam). In most places, patients with artemisinin-resistant infections recover fully after treatment, provided that they are treated with an ACT containing an effective partner drug. However, along the Cambodia-Thailand border, P. falciparum has become resistant to almost all available antimalarial medicines, making treatment more challenging and requiring close monitoring. There is a real risk that multidrug resistance will soon emerge in other parts of the subregion as well. The spread of resistant strains to other parts of the world could pose a major public health challenge and jeopardize important recent gains in malaria control.

A “WHO Strategy for Malaria Elimination in the Greater Mekong subregion (2015-2030)” was endorsed by all five countries, as well as China.

In 2010, an estimated seven per cent of people starting antiretroviral therapy (ART) in developing countries had drug-resistant HIV. In developed countries, the same figure was 10–20 per cent. Some countries have recently reported levels at or above 15 per cent amongst those starting HIV treatment, and up to 40 per cent among people re-starting treatment. This requires urgent attention.

Increasing levels of resistance have important economic implications, as second and third-line regimens are three times and 18 times more expensive, respectively, than first-line drugs.

Since September 2015, WHO has recommended that everyone living with HIV start on antiretroviral treatment. Greater use of ART is expected to further increase ART resistance in all regions of the world. To maximize the long-term effectiveness of first-line ART regimens, and to ensure that people are taking the most effective regimen, it is essential to continue monitoring resistance and to minimize its further emergence and spread. In consultation with countries, partners and stakeholders, WHO is currently developing a new “Global Action Plan for HIV Drug Resistance (2017-2021).”