Malaria: Description
Malaria is a serious disease, which is caused by the parasites transmitted to individuals through the infected mosquitoes’ bites (WHO, 2012). Malaria develops as a result of the bites caused by the so-called “malaria vectors” – mosquitoes that are infected with Plasmodium parasites (WHO, 2012). These mosquitoes attack potential victims mostly between dusk and dawn (WHO, 2012). Today, malaria remains one of the most prevalent life-threatening diseases in the sub-Saharan region of Africa. Despite the rapid development of international medicine, malaria continues presenting serious challenges to Africans, mainly due to the appropriate social conditions, poor access to medicine, poverty, as well as poor quality of anti-malaria drugs in Africa.
Malaria: Statistics
Statistically, malaria represents one of the major health problems affecting the Sub-Saharan region. Between 300 and 500 million attacks of malaria are registered globally every year (Keiser et al., 2004). Malaria causes almost 1 million deaths internationally, and the Sub-Saharan region accounts for the prevailing majority of these deaths (Keiser et al., 2004). 80% of disability cases that result from malaria are registered in sub-Saharan Africa (Keiser et al. 2004). In 2011, almost 655,000 deaths were caused by malaria, most of them affecting African children (WHO, 2012). Although mortality rates associated with malaria fell from 33% to 25%, it is still terrible that, every minute, one African child dies of malaria (WHO, 2012). As of today, 106 countries and territories are at high risk of malaria transmission (CDC, 2012). Malaria is a global problem, but its main burden is still on sub-Saharan Africa.
Malaria: Recent Decline
It should be noted, that the past years witnessed a considerable decline in the number and frequency of malaria cases in sub-Saharan Africa. Particularly in the past 3-5 years, many countries of Africa finally benefited from the rapid implementation of large prevention and control programs (O’Meara, Mangeni, Steketee, & Greenwood, 2010). The results of Eritrea and Ethiopia surveillance suggest that the rates of morbidity in these two countries have declined by almost 70% (O’Meara et al., 2010). Similar changes were observed in Rwanda, Kenya, Zambia, and Gambia (O’Meara et al., 2010). The most successful were control and prevention interventions on the island territories; in the meantime, the current state of malaria in large African territories remains unknown (O’Meara et al., 2010). The causal link between the reductions in malaria morbidity and specific interventions is often questionable (O’Meara et al., 2010). However, it is clear that the success and effectiveness of such interventions become more tangible, when implemented at the earliest stages of the disease.
Malaria: Clinical Causes
The main cause of malaria is the Plasmodium falciparum parasite (Gyatt & Snow, 2004). “Most P. falciparum infections occur in sub-Saharan Africa, and the P. falciparum parasite has been shown to be more common in pregnant than non-pregnant women and to have a substantial adverse effect on pregnancy outcome” (Gyatt & Snow, 2004, p.760). In case of pregnant women, parasite sequestration takes place in the placenta, although the exact mechanism of this process remains unclear (Gyatt & Snow, 2004). Other parasites that may cause malaria include: P. vivax, P. malariae, and P. ovale (WHO, 2012). In recent years, cases of malaria caused by a relatively new parasite, P. knowlesi, were registered: this species used to be responsible for malaria in monkeys (WHO, 2012).
Malaria: Clinical Signs and Symptoms
Malaria can manifest with a broad range of symptoms, which can also be absent (CDC, 2012). Although life-threatening, malaria is absolutely curable, if detected and treated without any delay. The incubation period in most cases ranges between 7 and 30 days (CDC, 2012). The longer the delay between exposure and symptom development, the more likely are the risks of misdiagnosis (CDC, 2012). More often than not, the exact symptoms and signs depend on the severity of the disease. Uncomplicated malaria is a classical malaria attack, which lasts from 6 to 10 hours and includes fever, chills, nausea, headaches, sweats and vomiting, body aches, and general malaise (CDC, 2012). The diagnosis is confirmed on the basis of blood tests (the presence or absence of parasites). Severe malaria is complicated by organ failures and other abnormalities in the patient’s organism. The latter may include severe anemia, cerebral malaria, acute respiratory difficulties, low blood pressure, acute kidney failure, etc. (CDC, 2012). Severe malaria is always a medical emergency.
Malaria Transmission
Transmission occurs exclusively through the Anopheles mosquitoes’ bites (WHO, 2012). The risks and intensity of transmission are related to many factors, such as the type of parasite, the host and vector, as well as the environment in which transmission occurs (WHO, 2012). As of today, 20 different kinds of Anopheles exist in the world, and all of them attack the human host at night (WHO, 2012). Africa has always been at increased risks of malaria, due to the fact that the mosquito lifespan in this region is longer, and they prefer biting humans rather than animals (WHO, 2012). Human immunity is an essential factor mediating the risks of malaria transmission (WHO, 2012). This partly explains why the youngest age groups are at the highest risks of malaria (Carneiro et al., 2010).
HIV and Malaria
The Human Immunodeficiency Virus (HIV) is traditionally considered as one of the most prevalent factors in malaria transmission. “Mounting evidence has revealed pathological interactions between HIV and malaria in dually infected patients” (Abu-Raddad, Patnaik & Kublin, 2006). In sub-Saharan Africa, the difference in risks among HIV-infected and non-HIV individuals was estimated at 28% (Korenromp et al., 2005). In other words, individuals living in sub-Saharan Africa and diagnosed with HIV are 28% more likely to get infected with malaria. Most probably, differences in the immune statuses among HIV-infected and non-HIV individuals account for the difference in their susceptibility to malaria.
Understanding Malaria Transmission: Problems
Understanding the patterns and elements of malaria transmission in the sub-Saharan region is critical for everyone, who seeks a deeper insight into the scope and magnitude of the malaria problem. This knowledge can help to identify the most relevant risks of disease in specific population groups and contribute to the development of appropriate prevention and control strategies. Unfortunately, at present, variations in research methods and analytical procedures have made it extremely difficult to measure and evaluate the patterns of malaria transmission dynamics across various regions (Kelly-Hope & McKenzie, 2009). Simultaneously, considerable variations in malaria transmission have been identified between urban and rural territories (Kelly-Hope & McKenzie, 2009). No less important are the considerations of mosquito phenotypes, species, climatic parameters in which they develop, and population density (Kelly-Hope & McKenzie, 2009). All these factors should be considered when strategies for malaria prevention and control in sub-Saharan Africa are being developed.
Malaria Treatment
Early detection and treatment are the two successful factors of malaria recovery in all population groups. As of now, the best available treatment for malaria, especially when caused by P.falcipartum, is artemisinin-based combination therapy (WHO, 2012). However, according to WHO (2012), it is also imperative that the cases of malaria are confirmed, by using rapid diagnostic tests or standard microscopy (WHO, 2012). It usually takes 15 minutes or less to confirm or rule out the diagnosis. At the same time, the treatment provided will depend on the severity of the diagnosis and other factors, such as the geographic location where the patient was infected, his/her immune status and health complications, etc. (CDC, 2012). It is also possible that the patient’s organism will resist to certain types of drugs (CDC, 2012). The weight, age, and pregnancy status of patients should also be considered.
Malaria in Africa: Chloroquine
In sub-Saharan Africa, chloroquine was introduced in the early 1940s and soon became the most widely spread medicine against malaria (Nuwaha, 2001). “It was the mainstay of presumptive and mass treatment in the malaria eradication campaigns, but it also largely replaced quinine in those areas where no systematic malaria eradication programs were conducted” (Nuwaha, 2001, p.2). With time, most regions in sub-Saharan Africa started to display the signs of chloroquine resistance, which greatly contributed to the growing mortality and morbidity from malaria (Nuwaha, 2001). The first reports of failure to treat malaria with chloroquine came in the 1960s and, by the 1980s, the scope of the chloroquine resistance in Africa was almost equal to the scope of the P.falciparum threat (Nuwaha, 2001). The emergence of the chloroquine resistance was further coupled with the use of poorly effective drugs (Nuwaha, 2001). As a result, thousands of children in sub-Saharan Africa developed anemia and parasitemia, whereas case-fatality rates reached unprecedented 18% (Nuwaha, 2001). The resistance was also associated with severer malaria outbreaks during the most problematic seasons, giving rise to the popularity of self-medication.
Self-Treatment in sub-Saharan Africa
Self-medication and self-treatment remain the two major problems related to malaria in sub-Saharan Africa. In certain parts of sub-Saharan Africa, the rates of self-treatment in malaria are sometimes as high as 94% (Nuwaha, 2001). 75% of the population in sub-Saharan Africa lives in rural territories, and it comes as no surprise that so many people apply to self-medication. Self-treatment is rarely adequate; overdosing and drug resistance become more common (Nuwaha, 2001). Additionally, not all medical professionals in sub-Saharan Africa believe in the validity and importance of diagnostic tests: microscopic diagnoses are rarely available and, when patients have a history of fever or malaria, presumptive treatment is the most common (Nuwaha, 2001). Africa is facing the lack of effective drug alternatives to deal with malaria more productively.
Poor Quality of Antimalarials: Statistics
Poor quality of anti-malaria drugs is one of the greatest problems facing sub-Saharan Africa. The availability and effectiveness of most anti-malareal drugs in the sub-Saharan region are highly questionable. The survey of 21 countries in sub-Saharan Africa has shown that the quality of antimalarial samples does not match the expected standards of quality. 35% of the antimalarial drug samples failed chemical analysis (Nayyar, Breman, Newton & Herrington, 2012). 15% of all drug samples have low effectiveness ingredients, whereas another 25% have excessive pharmaceutical elements (Nayyar et al., 2012). The quality of packaging in almost one third of antimalarial drug samples is extremely poor (Nayyar et al., 2012). Unfortunately, the current state of clinical information does not allow determining the exact proportions of substandard antimalarial drugs used by sub-Saharan populations (Nayyar et al., 2012).
Factors Contributing to Poor Drug Quality
Poor quality of antimalarial drugs is definitely one of the most serious factors affecting the relevance of the antimalarial medical care provided by hospitals in sub-Saharan Africa. “Antimalarial drugs comprise 25% of the drugs consumed in malarious countries, and when these drugs are of poor quality, they afflict the most vulnerable populations” (Nayyar et al., 2012, p.492). Numerous factors contribute to the poor quality of antimalarial drugs in sub-Saharan Africa. These factors include but are not limited to: self-prescription and self-treatment, problems with quality testing, poor regulations and control in the drug sector, the lack of effective drug legislation, prevalence of small drug companies with little knowledge of effective drug manufacturing, expensive quality drugs, erratic supply, and others (Nayyar et al., 2012).
Counterfeit Antimalarials
The most serious is the growing availability of counterfeit antimalarial drugs, which do not benefit but, on the contrary damage the state of public health in sub-Saharan Africa. The analysis of counterfeit antimalarial drugs from the 8 sub-Saharan regions suggests that criminals are devising new methods and means to produce diverse antimalarial counterfeits (Newton et al., 2011). The sub-Saharan region is characterized by the presence of numerous counterfeit medicines, which are used a part of the artesunate therapy but do not bring any tangible results. The use of unexpected anti-malarials threatens public health in sub-Saharan Africa and can readily result in the development of drug resistance (Newton et al., 2011). The rates of covert consumption of counterfeit anti-malarial drugs continue to grow, which further confuses professional understanding of the malaria health problem. There is still no evidence to confirm that counterfeit antimalarials are produced in Africa, although a number of illegal manufacturing facilities have been seized in Nigeria (Newton et al., 2011).
Substandard Antimalarial Drugs
Counterfeit drugs should be distinguished from the substandard mixtures, although both greatly impact the safety and health of sub-Saharan residents. Counterfeit drugs are those, which are intentionally mislabeled with regard to their source and actual identity (Amin & Kokwaro, 2007). Simply stated, counterfeit drugs used against malaria in sub-Saharan Africa claim to be what they are actually not (Amin & Kokwaro, 2007). In the meantime, substandard drugs simply do not match the established standards of medical quality and safety criteria, and substandard drugs are a bigger problem for malaria in sub-Saharan Africa than counterfeit products. Most antimalarials in sub-Saharan Africa are substandard, not counterfeit, due to the absence of good manufacturing practices (Amin & Kokwaro, 2007). Substandard drugs have far-reaching impacts on public health in Africa, resulting in various adverse reactions and causing sub-therapeutic levels of the target medicine in plasma (Amin & Kokwaro, 2007).
Combination medical therapy raises many concerns in sub-Saharan Africa. Apart from the poor quality of antimalarials, it is still not obvious what types of drugs should be used in sub-Saharan Africa (Bloland, Ettling & Meek, 2000). As of today, people in sub-Saharan Africa face the severely limited pharmacopeia of effective and affordable antimalarials, which hinders the development of new therapeutic strategies (Bloland et al., 2000). The potentials of combination therapy against malaria in sub-Saharan Africa are questionable, simply because the most effective drugs are expensive, and those which are less expensive are either of poor quality of simply counterfeit.
Treatment and Drug Quality Dilemma
The dilemma of treatment and drug quality in sub-Saharan Africa is very serious. Two treatment paradigms have historically been used in malaria treatment. First, the application and quality of antimalarials can improve at the expense of limited access to these drugs due to their cost (Bloland, Kachur & Williams, 2003). Second, it is still possible to minimize the barriers to obtaining quality anti-malarial treatment, while also sacrificing the power of control over drug supplies (Bloland et al., 2003). Reconciling these paradigms is possible, with the help of pre-packaging, quality labeling, improved education, and increased participation of drug sellers in the antimalarial drugs supply. Even in the presence of quality and affordable medical care, the poor quality of antimalarial drugs will remain a source of serious negative effects on health. Therefore, any strategies developed to deal with the malaria problem in Africa will have to be based on the controversial social and medical realities in sub-Saharan Africa.
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