WHO and partners make fresh commitments to end neglected tropical diseases. India, battling leprosy, dengue and chikungunya, has high stakes
A giant yellow inflatable schistosomiasis worm, with ‘Making Schistory’ printed on it, floated on Lake Geneva, marking the five years since the London Declaration on neglected tropical diseases (NTD). Though in 2015 about 1.59 billion people received treatment for at least one of the 18 diseases that constitute NTD, blinding, maiming, disfiguring and debilitating their victims, the global attention on the subject has waned over the years.
The reasons for this are not difficult to fathom. NTD affect the most impoverished people of the world, finding refuge in dirty shanties and filthy environments with abundant insects and vectors. Most of the NTD have been wiped out from the developed world. More than 70 percent of countries and territories that report the presence of NTDs are low or lower-middle income economies. They don’t, by and large, affect people who can afford expensive medicines and vaccines. Moreover, with the advent of HIV/AIDS, the huge increase in incidence of non-communicable diseases like cancer, and the devastating death rates from malaria and tuberculosis, majority of the donors’ funding has been diverted towards tackling these ailments. And it sure does not help that NTD have complicated names like lymphatic filariasis and onchocerciasis that are difficult to hook on to the layman’s imagination.
Progress so far
Nonetheless, there has been much progress in the past two decades. The prevalence rate of leprosy has dropped by 99 percent and with the exception of a few countries (India is one of them) the disease has been eliminated. In May 2016, WHO declared India free of yaws. The lowest level of the incidence of sleeping sickness – since systematic global data-collection began 76 years ago – was reported in 2015 with 2,804 new cases, though the estimated population at risk is 65 million people. More than 114 million people received treatment for onchocerciasis or river blindness which is about 62 percent of those requiring treatment. Only 25 human cases of Guinea-worm disease were reported in 2016, putting eradication within reach. For visceral leishmaniasis (VL), in 2015, the target for elimination was achieved in 82 percent of sub-districts in India, 97 percent of sub-districts in Bangladesh, and in 100 percent of districts in Nepal. These are some of the positive statistics.
“Since 2007, when a group of global partners met to agree to tackle NTDs together, a variety of local and international partners have worked alongside ministries of health in endemic countries to deliver quality-assured medicines, and provide people with care and long-term management,” says the World Health Organisation (WHO).
In 2012, in the London Declaration on NTD, 13 pharmaceutical companies alongwith governments and other donors pledged additional support and resources pushing for the control or elimination of an additional nine NTDs. There have been mass drug administration programmes and preventive chemotherapies where the entire population has been treated without being tested for infection. Improved hygiene drives, insecticide spraying, distribution of mosquito nets that prevents mosquito-transmitted lymphatic filariasis have all contributed in arresting the spread of NTD.
Since the launch of the London Declaration, the global NTD programme has grown into the largest medical donation programme in the world and by January 30, 2017 industry partners around the globe made a collective donation of more than 200 million NTD medication doses on this single day which created a new Guinness record for the maximum number of doses donated in 24 hours.
In Geneva, the WHO launched a global partners meeting on NTD on April 19. The WHO director-general Margret Chan was seen seated with former UN secretary-general Kofi Annan on her right and billionaire-businessman, and co-chair of Bill and Melinda Gates Foundation, Bill Gates on her left. The fourth report on NTD was launched on the occasion, which was attended by government representatives, donor organisations, NGOs and pharmaceutical companies to make new commitments to end NTD. Bill Gates announced an additional $330 million towards fighting NTD, while the British government represented by Priti Patel announced an additional $205 million and the Belgian government donated an additional $27 million. There was no ministerial level participation by the Indian government, though there was representation from the Directorate General of Health Services.
The Indian NTD landscape
Among the 18 NTD, the ones that are of concern to India are leprosy, dengue, chikungunya, VL and zoonotic diseases.
Since the definition of “eliminated” means an occurrence of fewer than one in 10,000 people, leprosy was officially declared as “eliminated” as a public health concern by the WHO in 2005. However, some areas including West Bengal, Odisha, Delhi, have high prevalence of leprosy. The declared status of leprosy as eliminated proved to be a disaster where progress stalled and funds and resources declined – compared to pre-2005 funding levels of about $8 million plus free medicines from pharmaceutical giants, India now receives about $2.5 million from one donor for its leprosy programmes.
An international daily reported a few days back that “during a two-week detection campaign organised by the NLEP [National leprosy eradication programme] at the end of 2016, more than 1,000 cases were discovered in nine states”, prompting the Indian government to reverse its “elimination” status for Odisha, Delhi, Chandigarh and Lakshadweep.
Though prime minister Narendra Modi has doubled the funding for leprosy programmes, according to the current WHO estimates, India was one of the few countries to record an increase in leprosy cases from 1,25,785 to 1,27,326 between 2014 and 2015.
VL or kala-azar is another area of concern for developing countries. The latest WHO report on NTD praises India, Bangladesh and Nepal for their efforts in combatting VL and bringing the rates down by 82 percent through improvement in vector control, social mobilization of village volunteers and drug donations from industry partners.
The Indian government recently announced that it wants to do away with VL by the end of this year – something health experts feel is a little too ambitious. The WHO has set its target for 2020.
Kala-azar caused by bites from female phlebotomine sandflies attacking the immune system is the second largest parasitic killer in the world after malaria. Bihar is one of the states where kala-azar is endemic, accounting for about 70 percent of the disease’s incidence in the country. An emerging concern for WHO is that VL often occurs as a co-infection with HIV, attacking a patient’s immune system. The six countries of India, Bangladesh, Brazil, Ethiopia, South Sudan and Sudan contribute more than 90 percent of the global burden of VL.
The third area that should be of considerable public health concern is the neglected zoonotic diseases – rabies, echinococcosis, taeniasis and cysticercosis, and foodborne trematodiases – a subset of NTDs that are naturally transmitted from vertebrate animals to humans and vice versa.
“The strategies of veterinary public health activities and the One Health approach recognize that the health of people is connected to the health of animals and the environment,” the WHO report states.
The greatest burden of endemic zoonoses falls on the 1 billion poor livestock keepers in Africa and Asia “who live in close contact with their animals and depend on livestock production for their livelihood and nutrition”. So the health of cows are equally important as that of chickens, ducks, goats and other livestock. The people who typically depend on livestock have the least access to services for human and animal health and to information.
Overcoming these diseases requires a multifaceted approach that bridges the human-animal interface, the report says.
“For example, it is not sufficient to focus rabies-control efforts on post-exposure prophylaxis for humans. It is also necessary to vaccinate dogs and implement waste management activities because, as with the other dog-transmitted NTDs, the management of waste has a direct impact on roaming dog populations. Thus, the involvement of multiple sectors is critical, including veterinary, water, sanitation and hygiene,” the UN’s health agency recommends.
In the case of rabies, worldwide there is one death every 10 minutes from dog bite which adds up to 160 deaths per day and 60,000 deaths annually of which 60 percent of the victims are children. Additionally, it is estimated that there are 3-5 million animal deaths per year from the dreaded viral disease.
About a third of these global deaths – 21,000 per year – occur in India.
The annual economic loss globally is about $8.6 billion from premature deaths, the cost of human post-exposure vaccines, lost income for victims of animal bites, livestock losses, and other costs and over 3.7 million disability-adjusted life years (DALYs).
Additionally, more than 29 million people receive post-bite treatment to prevent rabies at a direct cost of over $1.7 billion while India spends about $8.2 million in first-exposure treatment.
According to health experts, it is way cheaper for governments to engage in mass vaccination campaigns for dogs than to vaccinate or treat human beings after a bite. Contrary to popular notions, culling dogs may have very little or even detrimental impact on the rabies rate. This is true especially when there are concurrent dog vaccination campaigns. Then killing dogs means removing the protective buffer of transmission as the vaccinated dogs that are culled are quickly replaced by new unvaccinated population of puppies. Interestingly, domestic dogs cause over 99 percent of human rabies deaths. While more than 99 percent of human rabies is canine-mediated, it can also be transmitted through bats, foxes and raccoons.
Finally, vector-borne NTD like dengue and chikungunya should be of immense concern to India, also because of its potential link with Zika. While the vector-borne NTD include dengue, lymphatic filariasis, onchocerciasis, Chagas disease, leishmaniasis and human African trypanosomiasis, vectors of NTDs also carry other pathogens. Dengue, for example, is carried by the Aedes aegypti mosquito, which also carries the Zika and chikungunya viruses as well as other arboviruses.
According to WHO estimates, the major vector-borne diseases together account for 17 percent of the estimated global burden of communicable diseases and claim more than a whopping 7,00,000 lives every year. More than 80 percent of the global population lives in areas at risk from at least one major vector-borne disease and more than half of the world’s population is at risk from two or more.
The world has seen major outbreaks of dengue, chikungunya and Zika virus disease in all of the major WHO regions since 2014.
Zika is currently not listed as an NTD, but WHO is considering its inclusion, especially for its association with microcephaly and Guillain-Barré syndrome that severely affects unborn children from pregnant mothers affected by the virus. On February 1 last year, WHO had declared the Zika virus transmission to be a public health emergency of international concern.
“Increasing insecticide resistance, rapidly spreading arboviral diseases and the impact of climate change on vector distributions threaten to thwart the global gains made in controlling vector-borne diseases,” WHO says.
It is surprising that there has been no Zika virus outbreak in India till date though the virus had been detected in India in the early 1950s by the National Institute of Virology in Pune, even before the first virus was confirmed in Nigeria. Worryingly, blood tests have shown Zika antibodies in India, Pakistan and Thailand among other countries, indicating prior exposure to the virus.
“What any country that has got the Aedes and within the dengue belt should be concerned about is the possibility of the Zika virus arriving and that is what surveillance should be for, that is, the Zika virus arriving,” Bruce Aylward, WHO’s executive director for outbreaks and health emergencies had warned government of the dengue regions last year.
Although the vector can travel about 200 metres on its own, it hops on planes, boats and bamboos to criss-cross the world. The Zika outbreak last year had spread to more than 30 countries.
It is not clear at the moment whether the Zika virus is closer to dengue or chikungunya, WHO experts say.
This being the case, India could potentially be sitting on a ticking time bomb given the fact that the vector is abundantly present and there is a one billion at-risk population in the country.
(The article appears in the May 1-15, 2017 issue of Governance Now)