Major Biological Challenges in Pakistan

Research led by: Maheerah Nisar

Written By: Mohammad Ibrahim, Barirah Usman, Ibraheem Dar, Musfirah Naveed, Ayesha Irfan and Zahra

‍

Infectious Diseases       Malaria and dengue -Introduction: Several mosquito-borne infections are prevalent in tropical regions, with malaria and dengue among the most common and significant due to their high global morbidity and mortality. In Pakistan, malaria and dengue are endemic and seasonal diseases, with outbreaks frequently occurring after the monsoon season. Factors such as stagnant water, poor sanitation, and climate change contribute to increased transmission of these infections. Consequently, a substantial number of cases and deaths are reported, particularly in provinces such as Sindh, Khyber Pakhtunkhwa, and Balochistan. Furthermore, co-infections with malaria and dengue pose significant diagnostic and management challenges for healthcare systems.   -Main body: Malaria is a parasitic disease caused by protozoa of the genus Plasmodium and is transmitted to humans through the bite of an infected female Anopheles mosquito. Transmission commonly occurs in endemic areas, particularly in forested or rural regions. Following infection, affected individuals may develop symptoms such as high fever, chills, headache, and myalgia. In severe cases, malaria can lead to complications including intravascular hemolysis, jaundice, and acute kidney failure. Malaria is not transmitted directly from person to person, as transmission requires a mosquito vector. Types: 1. Plasmodium falciparum causes the most severe malaria, which can lead to cerebral malaria and death, with an incubation period of 7–14 days. 2. Plasmodium vivax usually causes less severe malaria but can recur due to long-term dormancy in the liver, with an incubation period of 8–14 days. 3. Plasmodium malariae causes chronic malaria infection and has an incubation period of approximately 18–40 days. 4. Plasmodium ovale is a type of malaria parasite that can remain latent in the liver for many years after infection. 5. Plasmodium knowlesi is a rapidly progressing malaria parasite transmitted from macaques to humans by Anopheles mosquitoes and can remain dormant for many years. Treatment for malaria: Malaria is primarily treated using antimalarial drugs, and the choice of therapy depends on the Plasmodium species, severity of infection, and regional drug-resistance patterns. The main objective of treatment is to eliminate the parasite from the bloodstream and prevent complications or relapse.   Artemisinin-based combination therapies (ACTs) are the first-line treatment for Plasmodium falciparum, as this species frequently exhibits resistance to older drugs such as chloroquine. ACTs combine artemisinin with another antimalarial agent to enhance efficacy and reduce the risk of resistance. For non-falciparum malaria (Plasmodium vivax, P. ovale, and P. malariae), chloroquine may be used in regions where resistance is absent. However, P. vivax and P. ovale can remain dormant in the liver, necessitating the use of primaquine to target hepatic stages and prevent relapse.   Severe malaria, particularly cerebral malaria, requires intravenous artesunate, followed by a full course of oral ACT once the patient stabilizes. Supportive care, including fluid management, fever control, and treatment of anemia or hypoglycemia, is also critical in managing severe cases.   -Main body: Dengue is a viral disease transmitted to humans through the bite of infected female Aedes mosquitoes, primarily Aedes aegypti and Aedes albopictus. Over recent years, the incidence of dengue has increased substantially due to rapid population growth, unplanned urbanization, and inadequate public facilities, including insufficient water supply and improper solid waste disposal, which promote breeding of the primary vector, Aedes aegypti. It is estimated that 100–400 million dengue infections occur annually worldwide, with approximately 80% of infected individuals remaining asymptomatic. Symptomatic dengue typically presents with high-grade fever, nausea, vomiting, abdominal pain, headache, myalgia, and periorbital pain. -Causes: Dengue fever is caused by any one of the four serotypes of the dengue virus. The disease is not transmitted through direct contact with an infected individual; rather, transmission occurs via the bite of an infected mosquito. The primary vectors responsible for the spread of dengue virus are Aedes aegypti and Aedes albopictus, which commonly inhabit areas in and around human dwellings. When a mosquito bites a person infected with the dengue virus, the virus enters and replicates within the mosquito. Subsequently, the infected mosquito can transmit the virus to another individual during a subsequent bite, allowing the virus to enter the bloodstream and cause infection.   --Treatment for dengue: No specific treatment for dengue fever exists. While recovering from dengue fever, drink plenty of fluids. The over-the-counter (OTC) drug acetaminophen (Tylenol, others) can help reduce muscle pain and fever. But if you have dengue fever, you should avoid other OTC pain relievers, including aspirin, ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve). These pain relievers can increase the risk of dengue fever bleeding complications. If you have severe dengue fever, you may need: ● Supportive care in a hospital ● Intravenous (IV) fluid and electrolyte replacement ● Blood pressure monitoring ● Transfusion to replace blood loss   -Challenges in Pakistan: The World Health Organization (WHO) estimates that approximately 400 million dengue infections occur annually worldwide, with nearly three-quarters of cases reported from Asia. In Pakistan, mosquito-borne diseases such as dengue and malaria are endemic, with over 350,000 reported malaria cases and 113 associated deaths in 2024. However, malaria is frequently misdiagnosed or underreported due to limited diagnostic resources and surveillance capacity. Consequently, the WHO estimates that the actual malaria burden may be significantly higher, with approximately 956,000 cases and 805 deaths occurring during the same period. Although malaria and dengue have generally remained under relative control in Pakistan in 2025, WHO reports indicate the occurrence of major outbreaks in specific regions. These epidemics commonly emerge during the post-monsoon season, largely due to prolonged water stagnation resulting from inadequate sanitation and sewage infrastructure across much of the country.   Polio Polio is an infectious disease which spreads from person-to-person. Modes of transmission can include excretions such as feces and saliva of the infected or direct contact with poliovirus carriers who may be asymptomatic. It can also be indirectly contracted from unhygienic environments, for example contact with contaminated surfaces or bodies of water. The virus is ingested through the mouth of the host and propagates in the intestines, it then invades and compromises the central nervous system through the spinal cord and brainstem, potentially causing irreversible paralysis. Its incubation period lasts 1-2 weeks after which the infected individual becomes capable of transmissiting the virus for 7-10 days before, and up to 7-14 days after symptoms. Clinical severity can be categorized into three classes, abortive, which is the mildest form where neurological symptoms are absent. Non-paralytic, where it has influence on the CNS but not enough to cause paralysis. And paralytic, being the most severe due to damage to motor neurons resulting in paralysis. Poliomyelitis exists in three types with type 2 and 3 declared eradicated while Wild Poliovirus Type 1 (WPV1) is still circulating primarily in Pakistan and Afghanistan. The most dependable method of prevention is through vaccination. It has proved its effectiveness by reducing polio cases by 99% since 1988. Proper sanitation can also prevent spread by limiting the contact with contaminated food, water and surfaces. Tuberculosis is another infectious disease, caused by Mycobacterium tuberculosis. Although it is contracted from prolonged exposure, it has caused one of the leading number of deaths (1.5 million per year) as an infection, with half of patients coming from developing countries like Pakistan, Bangladesh, China, India, due to overcrowding and poor ventilation in confined living spaces. The bacterium targets the lungs, therefore TB outside the lungs is typically non-contagious, so the main mode of transmission is through inhalation of the bacteria when a person coughs or sneezes. It can also develop secondary infections or conditions in other organs, for example, pott's disease, meningitis, hepatitis or scrofula, affecting the kidneys, liver, spine, brain and other organs. Tuberculosis is divided into types based on infectious status or location of the infection, active TB presents symptoms and is contagious because bacteria multiply constantly, while latent TB does not come with symptoms and is usually not contagious. The most common type by location is pulmonary TB which attacks the lungs, and then there is extrapulmonary TB which can manifest in other organs outside the lungs. The infection can be prevented by maintaining good hygiene, ensuring adequate ventilation in living spaces, and through the use of vaccination. Tuberculosis can be treated using a long course of antibiotics, which must be taken exactly as prescribed to prevent the development of drug-resistant strains. Common medications include isoniazid, rifampicin, pyrazinamide, and ethambutol.   Ecological Issues Climate Change and Nutrition: A Global Challenge Climate change is a major challenge for the world today. It affects not just the environment, but also the food we eat and our health. Climate change refers to long-term shifts in global weather patterns, primarily caused by human activities such as the burning of fossil fuels, deforestation, and industrial pollution. These actions increase greenhouse gases in the air. Climate and food systems are deeply connected. Climate change affects where food can be grown, how much is produced, and the nutritional value of that food. This, in turn, affects global nutrition, particularly for vulnerable populations that already face food insecurity. How Climate Change Affects Nutrition 1. Reduced Food Production Higher temperatures, unpredictable rain, droughts, and floods can lower crop yields and reduce livestock production. This means there is less food available, especially important foods like wheat, rice, and maize. 2. Lower Nutritional Quality Scientific studies have shown that elevated carbon dioxide (CO₂) levels can reduce the availability of essential nutrients in many crops. For example, higher CO₂ can lower protein, zinc, and iron levels in major food plants, making even sufficient calories less nutritious. 3. Food Access and Prices Extreme weather events and reduced yields make food more expensive and harder to access, especially for poor households. This increases the risk of malnutrition and food insecurity. 4. Health and Diet Patterns Climate change can affect what people eat and their health. It can lead to more foodborne illnesses and changes in appetite and food quality, which impact nutrition, especially for children and pregnant women. Why Nutrition Matters Good nutrition is essential for healthy growth, strong immunity, and cognitive development. When climate change disrupts food systems, people can suffer from undernutrition (lack of calories and nutrients) and micronutrient deficiencies, leading to weakened health, stunting in children, and increased disease risk. Solutions to Protect Nutrition 1. Sustainable and Resilient Agriculture Adopting climate-smart farming practices, drought-resistant crops, and improved irrigation helps maintain food production in changing climates. 2. Nutrition-Sensitive Policies Governments and organizations should include nutrition goals in climate policies, such as supporting smallholder farmers, improving food distribution, and investing in healthy food systems. 3. Reducing Emissions Limiting greenhouse gas emissions through renewable energy, forest protection, and sustainable land use can slow climate change and protect food systems. Conclusion Climate change is not just an environmental issue — it is also a nutrition crisis. Disrupting food production, reducing nutrient quality, and increasing food insecurity threaten people’s health across the globe. Sustainable solutions that link agriculture, nutrition, and climate action are crucial to ensure that all people have access to healthy, affordable food now and in the future. . Agricultural Impact on ecosystem The Use of Nitrogen: The use of nitrogen has increased over the past years and this has caused agriculture, climate, and other environmental issues.This has resulted in large increases of nitrogen in the environment, including nitrates in groundwater, runoff into rivers and coastal areas, and increases in the level of nitrogen oxides and nitrous oxide in the atmosphere. Nitrogen oxides and ammonium contribute to air pollution, with an estimated 19,000 people dying prematurely every year in the United States because of particulate matter caused by these and other agricultural emissions. Pesticides and Herbicides: Pesticides and herbicides kill pests and weeds. Pesticides kill undesired animals (pests), and herbicides kill undesired weeds.Pesticides can kill other animals. Intensive farming often uses pesticides which are toxic to other organisms within the ecosystem.These pesticides can get into the ground and can be carried to nearby river systems by rain water, where they can affect fish and other aquatic animals. Herbicides can kill other plants. Herbicides can kill other plants aside from weeds, which educes biodiversity of plants. It also affects any animals that rely on weeds for food. Fertilisers and Eutrophication: Use of fertilisers can lead to eutrophication.Fertilisers used by  farmers provide nutrients to help farmers promote good crop growth.The fertilizer are carried by rain water. These fertilisers can get mixed in with rain water which carries them to nearby bodies of water which then enter lakes and rivers. When the fertilisers get into lakes, rivers, and streams, they lead to a spike in nitrogen, ammonia, and other nutrients in the water. Nitrogen spike kills aquatic animals. This spike in nutrients and nitrogen is beneficial to aquatic plants which causes them to grow very rapidly and densely. However, nitrogen and ammonia are toxic to other aquatic organisms.Overgrowth of plants. The over growth of plants remove oxygen from the water.Large loss of aquatic animals. Ultimately, eutrophication leads to large scale die off of aquatic organisms, and eventually the plants themselves. Habitat Destruction: Converting forests, wetlands, and grasslands for farms destroys habitats, a main cause of species extinction, with agriculture responsible for much of the world's deforestation.   Invasive species Invasive species are non-native organisms (plants, animals, microbes) that spread rapidly in a new area, causing harm to the local environment, economy, or human health by out-competing natives, altering habitats, and disrupting ecosystems. They differ from other non-native species because they actively cause damage, often thriving due to a lack of natural predators, and can lead to biodiversity loss and significant financial costs for management. Examples include zebra mussels, kudzu, and Burmese pythons, introduced accidentally or intentionally, that disrupt food webs and clog infrastructure.   Population Growth, Poverty and Malnutrition Pakistan is one of the most populous countries globally, currently home to around 245 million people, accounting for nearly 3% of the world's population. This rapid population growth, which has increased significantly since the country gained independence, poses major biological challenges. The sharp rise in population has strained healthcare resources, compromised nutritional standards, and increased the prevalence of disease. In Pakistan, relentless population growth places immense pressure on the healthcare system. The public sector is chronically unable to meet the health needs of the population, resulting in government hospitals and primary care clinics consistently operating beyond capacity. At the same time, the private healthcare sector remains prohibitively expensive for a large proportion of the population. This mismatch between supply and demand, aggravated by underfunding and inadequate resources, severely compromises patient care. As a result, shortages of hospital beds, prolonged waiting times, and a lack of essential medical equipment are common, particularly in underserved rural areas. People living in poverty are especially vulnerable to economic instability, with approximately 52% of the country's population at risk of falling deeper into poverty. This vulnerability has profound biological consequences. Limited financial resources often lead to poor nutrition, increasing rates of malnutrition and susceptibility to disease. Over the past decade, Pakistan has also witnessed a significant rise in non-communicable diseases, such as ischemic heart disease and stroke. These conditions require long- term management rather than a cure, leading to increased healthcare costs and a growing health burden. Moreover, air pollution-both indoor and outdoor-plays a critical role in worsening health outcomes. It not only intensifies respiratory and cardiovascular diseases but also reduces labour productivity and diminishes human capability. This decline negatively impacts educational performance and overall quality of life, ultimately prolonging the cycle of poverty. Pakistan continues to face serious challenges related to nutrition and food security. Although some progress has been made in addressing malnutrition, food insecurity remains widespread. High food prices, climate-related shocks, and limited economic opportunities further exacerbate the issue. The condition known as wasting, in which children become severely underweight and emaciated, is alarmingly prevalent, with several regions classified at emergency levels. Despite the proven effectiveness of treatment programs-achieving recovery rates above global standards-these initiatives currently reach less than 5% of affected children. Fortunately, there are notable improvements that can significantly enhance the quality of life and health outcomes in the country. By educating more people, especially those in rural areas, about reproductive health, biological challenges related to high birth rates can be addressed. Low literacy and limited access to information contribute to misconceptions about contraceptives, which in turn affect population growth and health outcomes. Overcoming these barriers and providing accurate information will allow for informed decisions about family planning, ultimately reducing biological strain on healthcare systems and improving overall population health. Another primary strategy involves significant investment in the public health sector to bridge the current supply- demand deficit. This would include expanding infrastructure, increasing bed capacity, and ensuring consistent access to essential medicines and diagnostic services. At the same time, policies should be developed to improve the affordability of private healthcare. Furthermore, tackling malnutrition is essential. Solutions must prioritise targeted nutritional education and intervention programmes to improve dietary diversity and ensure adequate caloric intake, thereby reducing stunting and wasting at a population level. References [1] WHO. Dengue and Severe Dengue. 2023. [Last Cited: 19th Mar 2024]. Available at: https://www.who.int/news-room/fact-sheets/detail/dengue-and-severe-dengue. [2] Bhatt S, Gething PW, Brady OJ, Messina JP, Farlow AW, Moyes CL et al. The global distribution and burden of dengue. Nature. 2013 Apr :496(7446): 504-7. doi: 10.1038/nature12060. [3] Brady OJ, Gething PW, Bhatt S, Messina JP, Brownstein JS, Hoen AG et al. Refining the global spatial limits of dengue virus transmission by evidence-based consensus. PLOS Neglected Tropical Diseases. 2017 Aug; 6(8): e1760. doi: 10.1371/ journal.pntd.0001760. [4] WHO. Malaria-Pakistan. 2022. [Last Cited: 19th Mar 2024]. Available at: https://www.who.int/ emergencies/disease-outbreak-news/item/2022- DON413 Sahu PS, Sahu M, Ambu S. A review of concurrent infections of malaria and dengue in Asia. Asian Pacific Journal of Tropical Biomedicine. 2016 Jul; Shanks GD and White NJ. The activation of vivax malaria hypnozoites by infectious diseases. The Lancet Infectious Diseases. 2013 Oct; 13(10): 900-6. doi: 10.1016/S1473-3099(13)70095-1. https://my.clevelandclinic.org/health/diseases/15655-polio https://www.cda.gov.sg/professionals/diseases/poliomyelitis/ https://www.childrenshospital.org/conditions-treatments/polio#:~:text=Abortive%20poliomyelitis:%20The%20mildest% 20form,breathing%20muscles%20and%20leg%20muscles. Fanzo J. et al., Global Food Security: Effects of climate change across food systems and nutrition outcomes. UEA Climate Centre: Higher CO₂ reduces protein and minerals in crops. FAO/UN climate, food security, and nutrition overview. Krishnamurthy & Choularton: Climate impact on food access and price. PubMed: Climate change, food intake, and dietary patterns. PubMed: Cross-sectoral nutrition and climate adaptation strategies https://www.nationalacademies.org/read/26007/chapter/6#10 https://studymind.co.uk/notes/factors-affecting-biodiversity/ https://www.theigc.org/blogs/climate- priorities-developing-countries/how- environmental-risk-factors-affect-health- and https://indushospital.org.pk/impact/ newsroom/health-under-pressure- population-growth-challenges-and- solutions-for-pakistans-healthcare/ https://pmc.ncbi.nlm.nih.gov/articles/ PMC10548490/ https://www.unicef.org/pakistan/ nutrition-0

‍