Climate change and neglected tropical diseases

Khalid Md. Bahauddin
Recent investigations attribute more than 150,000 deaths per year and a global disease burden to climate change. An area that has received particular attention is the potential impact of global warming on shifts in the spatio-temporal distribution of disease vectors, and hence the frequency and transmission dynamics of vector-borne diseases. Vectors, pathogens (parasites), and hosts survive and reproduce within certain optimal climatic conditions. Changes in climate will alter the transmission of vector-borne diseases in different ways, such as changing the survival and reproduction rate of the vector and of the pathogen (parasite).
Public health officials often use the term tropical diseases to refer collectively to a list of infectious diseases that are found primarily in developing countries. These include malaria, schistosomiasis, dengue, trypanosomiasis, leprosy, cholera, and leishmaniasis, among others. Many of these diseases are spread by insect vectors, and all of them disproportionately affect the world’s poor. The World Health Organization estimates that neglected tropical diseases affect over one billion people each year and cause about 570,000 deaths annually. For example, some 200 million people are currently infected with schistosomiasis, a parasite that is transmitted through poor sanitation. More than 1.5 billion of the world’s poorest people are affected by a range of bacterial and worm based diseases including trachoma, river blindness and lymphatic filariasis. But despite the numbers they affect, and their health and social consequences, these diseases attract less than one per cent of the total health funding for the developing world.
The potential impact of global warming on the transmission of the neglected tropical diseases has received insufficient attention from researchers and different organisation. The Intergovernmental Panel on Climate Change (IPCC) has specially investigated the changing burdens of infectious diseases that may result from climate change. One IPCC background report notes that: Climate plays a dominant role in determining the distribution and abundance of insects and tick species directly, through its effects on vector and parasite development, and indirectly through its effects on host plants and animals and land-use changes. Therefore, it is anticipated that climate change will have an effect on the geographical range and seasonal activity of vector species and, potentially, disease transmission.
Global attention to infectious disease is primarily focused on HIV/AIDS, tuberculosis and malaria, the big three, as they are called. Unfortunately, this attention has not extended to a group of parasitic and microbial diseases called the neglected tropical diseases (NTDs). NTDs affect the poorest individuals. They thrive under poor sanitary conditions, where clean water and food are unavailable and where insect vectors are abundant. Women, children and those geographically isolated from health care are particularly susceptible. Those in conflict-ridden areas are also particularly susceptible, due to the disruption of any health-care infrastructure. Aside from thriving in poverty, the NTDs are also said to be poverty-promoting, as they reduce worker productivity and impair childhood development, and, consequently, the future earning abilities of those children.
Bangladesh is highly vulnerable to climate change and its high population density. Floods and cyclones are some of the major challenges that the country faces. Higher temperatures including more extreme weather events and sea level rise are already evident in Bangladesh. One estimate is that the average increase in temperature in Bangladesh would be 1.3ºC and 2.6ºC by the year 2030 and 2075 respectively with respect to the base year 1990. Global warming will increase the intensity of southwest monsoon, which will, in turn, bring about catastrophic ravages like floods and have far reaching consequences on health. During and after floods, the water borne diseases increase due to heavy contamination of the surface water. Thus climate change could cause floods, break-down of sanitation system, and more water and food-borne diseases.
Bangladesh may be one of the worst hit countries of the world due to a predicted rise in sea level. The increase in salinity in underground water will affect the availability of fresh safe water. As a result, people will be more inclined to use unsafe, contaminated surface water and will contact various water borne infectious diseases. Incidence of vector-borne diseases are likely to increase as a result climate change. This may increase the human contact with the vectors responsible for spread of diseases like malaria, filaria, leishmania and dengue. Though the surveillance system is very weak with gross under reporting, 13 districts of Bangladesh are known to be endemic for malaria, 34 for filariasis and 45 for visceral leishmaniasis (VL). Dengue has been detected in all six divisional headquarters.
The impact of climate change on neglected tropical diseases is itself neglected. There is an urgent need for researchers and organisations to investigate further the potential impact of climate changes on the transmission of neglected tropical diseases. The findings of such research are required so that populations might be able to overcome the increased risks.

 

The writer is a fellow (Japan), environment, member, Bangladesh Society of Environmental Scientists and Bangladesh Solar Energy Society. E-mail: khalid_mbuddin@yahoo.com

 

Original article on The Daily Star

Related News

Waterways disappear as rivers die

World River Day today Rashad Ahamad Inland waterways, once the prime mode of transportation in Bangladesh, have declined fast as many rivers, canals, and other water bodies have disappeared in riverine Bangladesh over the past decades. Due to geographical location, inland waterways were the main mode of transportation in Bangladesh, a country part of the ... Read more

Chattogram city produces 249 tonnes of plastic waste every day

Will generate 428 tonnes by 2052 News Desk : dhakamirror.com Chattogram city produces 249 tonnes of plastic waste every single day — 56 percent of which remains uncollected and littered in the environment, according to a new study. “Of the plastic waste, the most are sachets, single-use utensils, and personal care items, ” the study ... Read more

Non-stop river pollution threatens water security

World Environment Day Non-stop river pollution threatens water security Laws, rules, HC directives go in vain Rashad Ahamad No pragmatic step is yet to be taken to protect the four rivers surrounding Dhaka even after declaring them ecologically critical 13 years ago. In September 2009, the Department of Environment declared the four rivers Ecologically Critical ... Read more

Air pollution takes 3 years off life in Bangladesh

Impact on life expectancy in Bangladesh worse than in India, Pakistan, Bhutan Mohammad Al-Masum Molla Air pollution cuts the average life expectancy of a person in Bangladesh by almost three years, said a global report. It is higher than in India, Pakistan, Bhutan, and Afghanistan. Nepal, with air pollution-linked life expectancy loss of 3.05 years, ... Read more

Rain at the summit of Greenland for the first time on record

Something extraordinary happened recently. On August 14, 2021, it rained at the highest point on the Greenland Ice Sheet for several hours — the first rainfall event in recorded history, and air temperatures remained above freezing for about nine hours. The record-breaking rain is the latest in a string of warning signs about how climate ... Read more

Emissions of CO2 driving rapid oceans ‘acid trip’

The world’s oceans are becoming acidic at an “unprecedented rate” and may be souring more rapidly than at any time in the past 300 million years. In their strongest statement yet on this issue, scientists say acidification could increase by 170% by 2100. They say that some 30% of ocean species are unlikely to survive ... Read more

Warming trees limit warming – a little

Warmer temperature prompts trees to release aerosols which in turn stimulate cloud formation. And that can help to cool the temperature, at least modestly. Trees may provide the Earth with a little shade from global warming – indirectly. European and Canadian researchers report that they have found what engineers like to call a negative feedback ... Read more

Evaluating services of forest

Biodiversity contributes considerably to economy and environment Dr. M. A. BASHAR In developing countries, the necessity of publicising services of forests is severely lacking. This sector must be given attention with special emphasis. The country like Bangladesh has to be very serious in all respects to understand and exercise the services offered by the forests. We ... Read more

What the outcome yields for Bangladesh?

Doha Climate Conference What the outcome yields for Bangladesh? Md. Mahfujur Rahman Thirty-seven industrialized countries had been accused of releasing Greenhouse gases in Kyoto Protocol under United Nations Framework Convention on Climate Change (UNFCCC). Signatory members to the UNFCCC have been meeting annually in Conference of the Parties (COP) to assess progress in dealing with ... Read more

Down with the hills!

Probir Kumar Sarker Though Bangladesh is prominently a plain land, its Chittagong, Cox’s Bazar, Rangamati, Khagrachhari, Bandarban and Sylhet have hilly areas with forests and rich biodiversity. These areas are full of natural resources fulfilling needs of the people and other living species. But at present, the destruction of hills in every area has become ... Read more

A prerequisite for sustainable development

Natural Resource Governance A prerequisite for sustainable development Rukshana Sultana The constitution of Bangladesh — article 143– illustrates that all natural resources on land and underground minerals and other things of value underlying the ocean within the territorial waters, or the ocean over the continental shelf of Bangladesh, are the properties of Bangladesh. In general, ... Read more

Contemplating mitigation measures

Global Warming Contemplating mitigation measures Md. Atikur Rahman All things that make up the environment are interrelated. The way in which people, animals and plants are related to each other and to their surrounding is known as ecology. The ecosystem is a complex web that links animals, plants and every other life form in the ... Read more

Save Savar from further degradation

Probir Kumar Sarker Over the recent years, Savar is experiencing immense pressure of new industrial, commercial and residential establishments. But most of these have already been done or are underway indiscriminately haphazardly, and by violating the environmental laws and ignoring overall public convenience, not to speak of the care for future growth. It has been a ... Read more

Save Sonadia, save Sundarbans

Sourav Mahmud Sonadia Island is one of the biodiversity hotspot of Bangladesh. In 1995, the Government of Bangladesh included a provision for the declaration of Ecologically Critical Area (ECA) in the Bangladesh Environment Conservation Act. Twelve sites are classified as ECAs and guidelines exist to control further damage to these areas. Sonadia is considered ecologically ... Read more

Ramsar Convention: Our obligation

Dr. M.A. Bashar It is learnt from newspapers very recently that in the Sundarbans area three large constructions will take place which are very dangerous and detrimental to normal functioning of the mangrove forest ecosystem. It means that the interactions between biotic and abiotic factors will be seriously hampered in the ecosystems conservation. The projects ... Read more

Legal response to loss and damage

Climate Change Legal response to loss and damage Hafijul Islam Khan The adverse impacts of climate change have continued to devastate the lives and livelihoods of millions of people and inflict large economic losses. According to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, there has been a global increase in weather ... Read more

Corals of St.Martin’s at stake

Global Warming and Over-Exploitation Corals of St.Martin’s at stake Dr. Anisuzzaman Khan Honey comb corals around Saint Martin’s island are under stress due to coral bleaching. While the COP 17 — UN climate convention — was being held in Durban of South Africa, a Nature Watch Team (NWT) of Ekattor Television watched that a noticeable ... Read more

Environment: Future farmers hold key

GLOBAL food demand will double by 2050, according to a new projection, and the farming techniques used to meet that unprecedented demand will significantly determine how severe the impact is on the environment,  researchers say. The study researchers warn that meeting the demand for food will clear more land, increase nitrogen use and significantly add ... Read more

Getting a consensus in COP 17

How close the world is? Shammunul Islam The 17th United Nations Framework Convention on Climate Change (COP 17) will be held in the city of Durban, South Africa from November 28 to December 9. The world is waiting with hope that this time a fruitful and effective guideline will be made towards mitigating and adapting ... Read more

Pollution of rivers around Dhaka

Increasing threats to life Mohammad Tareq Hasan With a population of over 15 million Dhaka is one of the most congested cities of the world. This rapidly growing city is located on the northern bank of the river Buriganga and surrounded by other rivers, namely, the Turag to the west, the Tongi Khal to the ... Read more