Malaria's Dormant Threat: Unraveling The Mystery Of Its Persistence In Afghanistan

Afghanistan has the world's third-highest burden of malaria, with the disease being endemic in the country. Malaria is spread through the bite of an infected female Anopheles mosquito, which transmits the parasitic protozoons P. falciparum and P. vivax into the human body. The former is the most common cause of malarial incidence in the country, though cases have declined in recent years. The P. falciparum parasite can remain dormant in the liver for years before reactivating and causing malaria relapses.

Afghanistan's diverse landscape and terrain contribute to the heterogeneous malaria prevalence across the country. The disease is believed to be endemic in areas below 2,000 metres of elevation and highly prevalent in river valleys, where rice is grown.

Afghanistan has the world's third-highest malaria burden

Malaria in Afghanistan

Malaria is a vector-borne disease caused by the parasitic protozoon, Plasmodium, which is transmitted to humans through the bite of an infected female Anopheles mosquito. Afghanistan has four species of Plasmodium that cause malaria: P. falciparum, P. vivax, P. ovale, and P. malariae. P. falciparum and P. vivax are the major causes of malaria incidence in the country, with the former being more common and more severe.

Malaria transmission in Afghanistan occurs seasonally, from June to November, and the incidence varies based on human population density, behaviours, ecological factors, climate, agriculture, and access to health services. The disease is most prevalent in low-altitude regions where rice is cultivated and cattle farming occurs due to the favourable environment for the disease vectors. The eastern region of the country, particularly the provinces of Nangahar, Laghman, Kunar, Nuristan, Khost, and Paktika, has the highest malaria burden.

Challenges and Efforts

The civil conflict, lack of healthcare services, and the COVID-19 pandemic have resulted in a significant increase in malaria incidence in Afghanistan in recent years. Additionally, increased refugee movement and fluctuating environmental conditions have contributed to the proliferation of malaria vectors. Efforts to control the spread of malaria in Afghanistan have included the use of insecticide-treated nets (ITNs), larvicides, indoor spraying, and other biological and environmental methods.

The World Health Organization (WHO) and other organizations have provided technical and financial support to improve malaria surveillance and have distributed ITNs to high-risk communities. The Community-Based Malaria Management (CBMM) strategy, introduced in 2013, focuses on rapid diagnostic testing and timely treatment nationwide. However, despite these efforts, malaria incidence remains high due to insecurity, limited skilled staff, limited financial support, and weaknesses in the monitoring system.

Recommendations

To reduce malaria incidence, it is recommended to integrate malaria diagnosis and treatment into routine healthcare delivery and to broaden national strategies to include the health, agricultural, and private sectors. Additionally, vector control through management of potential breeding sites and increasing access to anti-malaria interventions such as ITNs, indoor spraying, diagnostics, and effective drugs is essential.

The country accounts for 11% of malaria cases in the WHO Eastern Mediterranean region

Afghanistan has the third-highest malaria burden in the world. The country accounts for 11% of malaria cases in the WHO Eastern Mediterranean region. In 2017, 91% of confirmed P. falciparum and 89% of P. vivax cases were reported from six provinces: Nangahar, Laghman, Kunar, Nuristan, Khost and Paktika. Nangahar province alone accounted for more than 45% of cases in 2019.

Afghanistan's high malaria burden is due to a combination of factors. The country's deteriorating healthcare system, mass relocations, civil conflict, and the COVID-19 pandemic resulted in a five-to tenfold increase in malaria incidence in recent years. The return of refugees from neighbouring countries, intensified rice cultivation near populated areas, and the lack of vector control measures have also contributed to the proliferation of malaria vectors.

The Eastern Mediterranean Region of the WHO includes countries such as Saudi Arabia, Yemen, Djibouti, Somalia, Sudan, and South Sudan, where P. falciparum is the predominant parasite. In Afghanistan, both P. falciparum and P. vivax are transmitted, with P. vivax accounting for 95% of cases.

The WHO has been actively supporting malaria control and elimination efforts in Afghanistan. In 2016-2017, around 2.8 million insecticide-treated bed nets (ITNs) were distributed to high-risk provinces. The Community-Based Malaria Management (CBMM) strategy, introduced in 2013, aims to provide rapid diagnostic testing and timely treatment at the community level. Since its implementation, CBMM has contributed to a significant reduction in malaria incidence and death rates.

Despite these efforts, insecurity, limited skilled staff, insufficient financial support, and weaknesses in the monitoring system continue to challenge malaria control in Afghanistan. To address these challenges, integration of malaria diagnosis and treatment into routine healthcare delivery is essential. National strategies should be broadened to include the health, agricultural, and private sectors to improve vector control, prevention, diagnosis, and treatment.

In Afghanistan, 5% of malaria cases are attributed to Plasmodium falciparum and 95% to Plasmodium vivax

Afghanistan has the world's third-highest malaria burden, accounting for 11% of cases in the WHO Eastern Mediterranean region. In Afghanistan, 5% of malaria cases are attributed to Plasmodium falciparum (P.f.), and 95% to Plasmodium vivax (P.v.).

P.f. and P.v. are the major causes of malarial incidence in Afghanistan, with the latter being less common and less severe. P.v. is the most dominant infection in Afghanistan, and the country's diverse landscape and terrain contribute to the heterogeneous malaria prevalence across the country.

In 2017, 91% of confirmed P.f. and 89% of P.v. cases were reported from six provinces: Nangahar, Laghman, Kunar, Nuristan, Khost, and Paktika. Nangahar province alone encompassed more than 45% of cases in 2019.

The transmission of malaria in Afghanistan occurs seasonally from June to November, and regional incidence varies based on human population density, behaviours, ecology, climate, agriculture, and access to health services for detection and treatment of malaria. Higher prevalence occurs in low-altitude regions where rice is cultivated and cattle farming occurs, due to the better environment for the zoophilic nature of the disease vectors.

The peak season for P.v. is in May/June-November, with negligible transmission between December and April. However, many P.v. infections relapse during the spring season, which may give rise to a peak of clinical cases. The P.f. peak is shorter and occurs in August-October.

The National Malaria and Leishmaniasis Control Programme (NMLCP) has found it challenging to find even 50 P.f. cases per year at the sentinel site for drug efficacy studies.

The treatment guidelines for P.v. have been guided by local evidence from clinical trials and are based on World Health Organization–Eastern Mediterranean Regional Office guidelines.

Insecticide-treated bed nets (ITNs) have been gradually accepted through extensive public awareness campaigns

Insecticide-treated bed nets (ITNs) have been instrumental in the fight against malaria in Afghanistan. As the country grapples with a deteriorating healthcare system, mass relocations, and civil unrest, malaria has become endemic, with over 150,000 cases reported in 2019 alone. ITNs have gradually gained acceptance as a critical vector control tool through extensive public awareness campaigns, becoming a favoured method for malaria prevention alongside insecticide spraying.

In the context of Afghanistan, ITNs have been particularly useful in refugee camps, where they have been introduced through subsidized sales, fostering sustainability and self-reliance in malaria prevention. This approach has been so successful that similar strategies are being considered for other chronic refugee situations worldwide. However, the acceptance and adoption of ITNs have faced challenges due to the complex social, economic, and cultural dynamics in the country.

One significant challenge is the affordability of ITNs, especially for large households. In Afghanistan, it is common for extended families to live together, resulting in household sizes of 20-30 people. For such families, purchasing enough ITNs to cover everyone can be prohibitively expensive. This issue is compounded by the seasonal income patterns that may not align with the availability of ITNs at the beginning of the malaria season.

Another barrier to ITN acceptance is the perception of their effectiveness and utility. Some individuals have expressed reluctance to purchase ITNs unless they can provide protection for their entire family. Additionally, cultural beliefs and practices may influence the adoption of ITNs. For example, in some communities, the idea of including ITNs as part of a dowry was met with amusement, suggesting that cultural norms may play a role in how ITNs are valued and perceived.

Despite these challenges, public awareness campaigns have played a crucial role in gradually increasing the acceptance and adoption of ITNs. These campaigns have likely contributed to the peak usage of ITNs during the summer months, which coincides with the peak malaria transmission season in Afghanistan. Furthermore, the success of ITNs in providing protection against malaria has been demonstrated in various studies, including a case-control study in Nangarhar, which found that ITNs were effective despite high temperatures during the summer and autumn.

In conclusion, insecticide-treated bed nets (ITNs) have become an essential tool in the battle against malaria in Afghanistan, and their gradual acceptance through extensive public awareness campaigns has been critical in reducing the impact of this life-threatening disease. However, ongoing efforts are still needed to address the challenges of affordability, cultural beliefs, and seasonal usage to ensure that ITNs reach those who need them most and contribute to a sustainable and effective malaria prevention strategy in Afghanistan.

The main transmission season for malaria in Afghanistan is from June to November

Afghanistan's main malaria transmission season is from June to November. The country's diverse landscape and terrain contribute to the heterogeneous malaria prevalence across the country.

The transmission of malaria in Afghanistan is seasonal and focal, occurring in areas below 2000 m in altitude, and in irrigated areas that allow the breeding of anopheline mosquito vectors. The main transmission season is from June to November, and transmission in other months is negligible.

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