Uncovering malaria in Bangladesh

Asifur Rahman01747137920North South University

Malaria is one of the major public health problems in Bangladesh. Out of 64 districts in the country 13 border districts in the east and northeast facing the eastern states of India and a small territory of Myanmar are in high endemic malaria zones, reporting about 98% of the total malaria cases every year.

Malaria

Malaria is caused by the plasmodium parasite. The parasite can be spread to humans through the bites of infected mosquitoes.

There are many different types of plasmodium parasite, but only five types cause malaria in humans. These are:

Plasmodium falciparum – mainly found in Africa, it is the most common type of malaria parasite and is responsible for most malaria deaths worldwide.

Plasmodium vivax – mainly found in Asia and South America. This parasite causes milder symptoms than Plasmodium falciparum, but it can stay in the liver for up to three years, which can result in relapses.

Plasmodium ovale – fairly uncommon and usually found in West Africa. It can remain in your liver for several years without producing symptoms.

Plasmodium malariae – this is quite rare and usually only found in Africa.

Plasmodium knowlesi – this is very rare and found in parts of South East Asia.

Causes of malaria 

Was first known as AGUE or MARSH FEVER•Italian: “aria cattiva ”= bad air; “mal aria”= bad air. Malaria

may have contributed to the decline of the Roman Empire and was so pervasive in Rome that it was known as the "Roman fever“. Several regions in ancient Rome were considered at-risk for the disease because of the favourable conditions present for malaria vectors.

•2700 BCE: The NeiChing (Chinese Canon of Medicine) discussed malaria symptoms and the relationship between fevers and enlarged spleens.

•Hippocrates from studies in Egypt was first to make connection between nearness of stagnant bodies of water and occurrence of fevers in local population.

•Romans also associated marshes with fever and pioneered efforts to drain swamps.

History

Symptoms of malaria typically develop within 10 days to four weeks following the infection. In some patients, symptoms may not develop for several months. Some malarial parasites can enter the body but will be dormant for long periods of time. Common symptoms of malaria include:

shaking chills that are moderate to severe high fever profuse sweating headache nausea vomiting diarrhea anemia muscle pain convulsions coma bloody stools

Symptoms

Malaria is a major public health problem in some parts of Bangladesh, particularly in 13 districts in the north-east & south-east areaswhich border India and Myanmar. In 2013 the prevalence rate of malaria was found to be 0.7% in these districts. About 80% of the total cases are reported from the three Chittagong Hill Tract (CHT) districts (Rangamati, Khagrachari and Banderban) including Chittagong and the coastal district Cox’s Bazar.

Malaria Situation in Bangladesh

Fig: Map of Bangladesh showing Malaria Endemic Areas

Total population of the three CHT districts is 1.6 million. The indigenous population constitutes about 50% of the total population in these districts. The tribal hamlets are in clusters in the remote hills and foothills and some are hard-to-reach due to lack of communication.

Most of the houses are thatched built with indigenous material e.g. bamboo, wood etc. and these houses seldom have any protection against the vector mosquitoes and thus peoples are vulnerable to malaria infection.

There are also higher risk of malaria transmission in the border areas, due to cross-border movement/migration across international boundaries with eastern states of India and part of Myanmar.

Four districts (Mymensingh, Netrakona, Sherpur and Kurigram) with eight endemic upazilas have low transmission of malaria and have shown <5% malaria positivity rates (RDT and Microscopy) over last three years. These districts currently may be considered for adopting pre-elimination strategies. The NMCP should have phased targets of elimination for these districts and gradually expanding to the other moderate endemic areas in near future. There is significant progress in malaria control in Bangladesh during the period from 2008 to 2013 showing a progressive decline in total cases and deaths.

The graph below shows the epidemiological trend of case incidence and deaths 2007-2013.

Malaria transmission in Bangladesh is a complex phenomenon due to the presence of multiple vectors each playing unique role for their vector bionomics and susceptibility to insecticides that should be taken into account in vector control.

There are four primary vectors (An philippinensis An minimus, An sundaicus and An baimai/An dirus), three secondary vectors (An vagus, An annularis and An aconitus) and at least two suspected vectors (An maculatus and An willmori)) with potential role in transmission in various parts of the country. These primary vectors of malaria were detected and confirmed since the malaria eradication period.

Vectors Prevalence and Transmission Potentials

Bangladesh has a tropical monsoon climate. The average rainfall varies from 119 to 348 cm.The alluvial soil of Bangladesh is continuously enriched by heavy silt-deposits during the rainyseason. The total forest area covers about 8 percent of the land area. With the Global Climate Change Bangladesh is likely to be more affected and there might be increased prevalence of vector borne diseases.

Most malaria cases are reported in three administrative regions (divisions) of Bangladesh .Mosquitoes are very sensitive to moisture and temperature, and their activities can be monitored by weather conditions. Three weather parameters are important for mosquito activity and malaria epidemiology: temperature, humidity, and rainfall. Temperature and humidity in Bangladesh are relatively stable from year to year. However, annual rainfall fluctuates between 2,000 and 3,000 mm.

Two seasons are defined in the annual cycle: a warm, wet season from April to October, and a cool, dry season from November to March. During the cool, dry season, mosquitoes are less active and the number of malaria cases is small. This number increases considerably during the warm, wet season.

Malaria Prone Time and Weather

Historically, the malaria control programme in Bangladesh had four phases: Malaria Eradication Programme (in early

1960s; Malaria Control Programme (1977-1994); Revised Malaria Control Strategies (RMCS-

1994); and Continuation of RMCS with updated

strategies until today.

Malaria control program

Malaria control programFigure: Malaria Programme in Bangladesh-Milestone Activities

Current activities are part of the existing National Strategic Plan (2008-2015) which envisaged 60% reduction of malaria morbidity and mortality (compared to baseline 2005) by 2015. Malaria National Strategic Plan (2015-2020 ) is being introduced to achieve ‘zero indigenous transmission’ and ‘zero death’ aiming malaria elimination in Bangladesh by 2020.

Use of LLIN and ITNsFigure: Mortality of Anophele Species to LLINs & ITNs

The LLIN namely BestNet (manufactured by Netprotect) supplied in 2013. Deltamethrin treated Polyethylene net and normal net dipped with K-O-TAB 1-2-3 (only Durgapur of Netrokona) were tested. The mortality rate for selected were found 36% (polyester) & 31% (Normal net) dipped with K O TAB-123 in Durgapur.

What is LLIN and ITN?An insecticide-treated net (ITN) is a net (usually a bed net), designed to block mosquitoes physically, that has been treated with safe, residual insecticide for the purpose of killing and repelling mosquitoes, which carry malaria. A long-lasting insecticide-treated net (LLIN) is an ITN designed to remain effective for multiple years without retreatment. The insecticide is cleverly bound within the fibres that make up the netting and is 'slow released' over a 4-5 year period.K-O Tab 1-2-3 is a 'dip-it-yourself' long-lasting formulation with time-limited interim recommendation from WHO for treatment of washed white and coloured polyester nets for up to 15 washes.

Use of LLIN and ITNs

Statistic: HEED Bangladesh signed in agreement with GFATM one of the principle recipients BRAC in May, 2008 to implement Malaria Control Project in Jaintapur Upazila in Sylhet district with a view to contribute in reducing malaria burden nationally by June, 2015.

Use of LLIN and ITNs

What HEED BD did is:1. LLIN: Total distributed

15500 and replaced 15500

2. ITN with KO tab123: Total bed net treated 19082 in 2011

3. House-to-house education for promotion and use of LLINs/ITNs

Organizational set up of the NMCP

Figure: Organogram of NMCP, DGHS

The NMCP had the GFATM support since 2007 and there was an increase in number of cases due to scaling up of interventions; introduction of RDR for diagnosis, and ACT for treatment of P. falciparum cases. Thereafter, a steady decline is noted from 84,690 cases in 2008 to 26,891 cases in 2013, having a 68.2% reduction in case incidence. The total deaths came down to 15 in 2013 as against 154 in 2008 showing 90.2 % reduction.

Clinical case reduction

Table: District-wise Epidemiological data (13 Districts, 2011-2013)

Malaria microscopy and RDT are the main tools for diagnosis in Bangladesh. Microscopy is usually used at static health facilities (n=83) and new microscopy centers (n=121) whereas RDT is used at the community level and in hospitals during odd hours.

Initially P. falciparum specific RDT was used which was replaced by Pan RDT very recently. RDT started to use in a mass scale from 2008 under the support of GFATM funding under round 6. At the community level ‘ShayasthoKarmi’ (health worker) and ‘Shayastho Shebika’ (community volunteer) of NGOs are responsible for diagnosis and treatment of uncomplicated malaria. The GoB Health Workers are also responsible for diagnosis and treatment of uncomplicated malaria using Pan RDT.

Diagnosis and Management of Malaria

There has been significant reduction of number of cases and deaths due to malaria over last few years. However, the proportion of P. falciparum malaria has been found to be rather increased (96%) due to wide scale use of mono-valent Pf-RDT and limited use of microscopy for diagnosis of P. vivax. In fact 7,303 cases were diagnosed by microscopy in 2013 of whom 953 were P. vivax infection out of total 26,891 reported cases. Introduction of Pan RDT is an important step as it would help to diagnose P. vivax cases in the community and will help to provide treatment as well.

Malaria is an entirely preventable and treatable disease. The primary objective of treatment is to ensure the rapid and complete elimination of the Plasmodium parasite from the patient’s blood in order to prevent progression of uncomplicated malaria to severe disease or death, and to prevent chronic infection that leads to malaria-related anaemia.

Treatment of Malaria

Treatment of P. falciparum infectionsWHO recommends artemisinin-based combination therapies (ACTs) for the treatment of uncomplicated malaria caused by the P. falciparum parasite. By combining two active ingredients with different mechanisms of action, ACTs are the most effective antimalarial medicines available today. P. vivax infections

It should be treated with chloroquine in areas where this medicine remains effective. In areas where chloroquine-resistant P. vivax has been identified, infections should be treated with an ACT, preferably one in which the partner medicine has a long half-life. Primaquine: 1 tab daily for 14 days in adults (1 tab- 15mg),0.3

mg/kg/daily for 14 days in children. Beside above mention drugs,WHO recommend others ACTs(eg. artemether plus lumefantrine, artesunate plus amodiaquine,,) for the treatment of uncomplicated malaria..

The Treatment are follows

Prevention & controlsPrevention of malaria involves protecting yourself against mosquito bites and taking antimalarial medicines. But public health officials strongly recommend that young children and pregnant women avoid traveling to areas where malaria is common.To prevent mosquito bites, follow these guidelines:1. Stay inside when it is dark outside, preferably in a screened

or air-conditioned room.2. Wear protective clothing (long pants and long-sleeved shirts).3. Use flying-insect spray indoors around sleeping areas.4. Avoid areas where malaria and mosquitoes are present if you

are at higher risk (for example, if you are pregnant, very young, or very old).

Prophyilaxis

All travellers to regions where malaria is endemic should be thoroughly educated regarding personal and environmental measures to provide protection against mosquito bites. These measures include use of repellent containing N,N-diethyl-3-methylbenzamide, use of long sleeves pants and footwear and or air-conditioned sleeping areas. The resistance of P. falciparum to chloroquine is nearly universal.

Malaria prevention in short-term travellers:

Currently, several antigen and adjuvant combinations have entered clinical trials, exposure to natural infection is evaluated. Vaccination trial done against different stages of malaria parasite such as pre-erythrotic stage {antigen-CSP (Circumsporozoite protein), LSA-1 (Liver stage antigen-1)}, Asexual stage {(AMA-1 (Apical membrane antigen-1), Sexual stage (Pfs25/Pvs25) and multistage antigen but sterile immunity was not observed in a large proportion. Vaccine development and field trials are lengthy and expensive.

Vaccination

The National Malaria Control Programme (NMCP), Bangladesh aims to achieve malaria elimination (‘zero indigenous transmission’ and ‘zero deaths’) by ensuring equitable and universal accesses to effective preventive and curative services to all ‘at risk population’ through concerted efforts of the GoB, NGOs, Private sectors, and the community. Achieving the goal of ‘Malaria Free Bangladesh’ will contribute to poverty alleviation as the poorest of the poor segment of the population are largely the victim of malaria.

By 2020, to have achieved ‘zero indigenous transmission’ and ‘zero death’ aiming malaria elimination in Bangladesh.

Mission, implementation and progress

To achieve 100% coverage of ‘at risk’ population with appropriate malaria preventive interventions by 2018

To have 100% malaria patients receiving early and quality diagnosis (RDT or Microscopy) and effective treatment by 2018

To continue strengthening of programme management towards elimination by 2020

To continue strengthening of disease and vector surveillance, Monitoring and Evaluation towards malaria elimination

To intensify Advocacy, Communication and Social Mobilization (ACSM) for malaria elimination

Objectives

The National Malaria Control Programme has received USD 29.70 million from GoB-HPNSDP during 2011-16 and USD 22.66 million from GF during 2010-15. The NGO-PR (BRAC and SRs) received USD 16.40 million and USD 15.21 million from GF, respectively during the period of 2007-2010-2015. For the period 2007-2014 the NMCP also received USD 1.76 million form the WHO regular biennial programmes for malaria control activities.

Malaria control cost

Table: Summary Budget of NSP 2015-2020 (USD Million)

Anti-malarial drug resistance:

The South Asian region has made considerable progress in reducing rates of malaria over the past 20 years, but last year’s data show that rates of malaria in Bangladesh are now increasing. According to the latest statistics, the total confirmed number of cases of malaria has risen from 29,518 in 2012, to 26,891 in 2013 and to 57,469 in 2014. Confirmed malaria deaths increased from 11 in 2012 to 45 deaths in 2014

Add to these threats the fact that there is a widespread and growing resistance to insecticides, and icddr,b’s, reasons could be many:

1. The increased mobility of Bangladesh’s population, both domestically and internationally, means that there will also be potentially severe implications for greater Bangladesh, for the region and for the rest of the world.

2. The improper administration of drugs is a big problem as well, because there is no way to ensure that people take the full course of anti-malarial drugs. They might take one or two doses out of six, but stop after their fever subsides.

3. When the drugs are not used properly—when the malaria parasite is not exposed for long enough, or it is exposed to too low concentrations of the drug—the parasite evolves to protect itself.

4. Detected mutations on the same K13 gene of the Plasmodium falciparum malaria parasite that is associated with the Cambodian-strain of artemisinin-resistant malaria.

ConclusionDespite these challenges, the Government of Bangladesh has pledged to eliminate malaria in Bangladesh by 2020 and the Asia-Pacific Malaria Elimination Network (APMEN) is committed to malaria elimination in the region by 2030. Malaria is also a priority disease for the Bill & Melinda Gates Foundation, a main funder of efforts toward malaria control and elimination. We caught up with icddr,b Scientist Dr Wasif Ali Khan and Assistant Scientist Mr. Shafiul Alam to find out what role icddr,b has to play in achieving these goals.

Reference

1. National Malaria strategic plan 2015-2020National Malaria Control Programme (NMCP), Communicable Disease Control Division, Directorate General of Health Services, Ministry of Health & Family Welfare.2. Maksudur Rahman, Hossain Shahid Kamrul Alam, Abu Tayeb, Probir Kumar Sarker,Tahera Nazreen, Akhand Tanzih SultanaMalaria - An update; DS (Child) H J 2011; 27 (2) : 83-87.3. 3. Dr Ubydul Haque, Hans J Overgaard, Archie C A Clements, Douglas E Norris, Nazrul Islam, Jahirul Karim, Shyamal Roy, Waziul Haque, Moktadir Kabir, David L Smith, Gregory E Glass 4. Malaria burden and control in Bangladesh and prospects for elimination: an epidemiological and economic assessment; The Lancet Global Health, Volume 2, Issue 2, February 2014, Pages e98–e105.