Recently outbreak of malaria in current world: species, etiology, life cycle, transmission, symptoms, vaccination, diagnostic tests, treatment, and complications
Md. Rezaul Islam, Puja S. Dhar, Md. Mominur Rahman
Abstract
Dear Editor, Malaria is a severe, occasionally fatal tropical disease that is brought on by a parasite and spread by mosquitoes. Over 445 000 people are killed by it every year, majority of them youngsters in Africa. Malaria can still be contracted when traveling to other regions of the world, despite the fact that it is all but eradicated in the USA. From immigrants and visitors returning from nations where malaria is more prevalent, the USA sees roughly 1700 cases of malaria each year1. Pakistan has an epidemic of malaria. In Pakistan, ∼3.4 million suspected cases of malaria were reported between January and August 2022 as opposed to 2.6 million between 2021 and 2022. Laboratory testing has identified over 170 000 instances, of which 77% are attributable to Plasmodium vivax and 23% to Plasmodium falciparum, which is associated with the most severe and fatal cases. P. falciparum is more fatalities. Following the severe floods in mid-June 2022, a sharp increase in cases was seen in the provinces of Balochistan and Sindh, which together accounted for 78% of all confirmed cases. The capability of the national health system is being affected by the present flood catastrophe, which raises concerns about the risk. Compared with the 19 826 cases recorded in August 2021, there were 68 123 confirmed malaria cases in Sindh Province in August 2022. As opposed to 22 032 confirmed cases in August 2021, 41 368 confirmed cases were reported in the Baluchistan Province in August 2022. In Pakistan in 2022, these two provinces collectively account for 78% of all reported confirmed cases. A total of 210 715 extra cases were reported in September 2022, according to reports from 62 high-burden areas, up from 178 657 cases in the same districts in August 20222. A protozoan parasite of the genus Plasmodium called a malarial parasite is a single-celled parasitic disease that cannot survive without its host. P. falciparum, which also accounts for the bulk of malaria-related fatalities globally, is the malaria species that infects people most frequently in sub-Saharan Africa. The other species are often not as deadly as P. falciparum. Southeast Asia and Latin America are also home to a large number of P. vivax, the second most significant species. In addition, Plasmodium ovale and P. vivax both have a latent liver stage that can reawaken in the absence of a mosquito bite and cause clinical symptoms. Plasmodium malariae and P. ovale make for a very minor percent of infections3. A mosquito bite carrying the Plasmodium parasite can result in malaria. The four distinct malaria parasite species that can infect people are P. ovale, P. malariae, P. vivax, and P. falciparum. People who contract P. falciparum have an increased risk of dying from the disease’s more severe form. In addition, a mother who has the disease may pass it on to her unborn child. The phrase used for this is congenital malaria4. (1) Female mosquitoes like Anopheles ingest human blood for egg generation during the life cycle of the malaria parasite. It’s interesting to note that in the parasite life cycle, the mosquito hosts and the human hosts are connected via these blood meals. In essence, human and female Anopheles mosquitoes become infected with malaria through cyclical contact. (2) Humans contract malaria when bitten by a mosquito carrying the Plasmodium parasite. The parasite is then allowed to run amok in their blood. The infected cells also rupture because they initially form and proliferate in the liver cells before moving on to the red blood cells. To complete the cycle, parasites that grow inside red blood cells create daughter parasites that infect other red blood cells. (3) The blood-stage parasites that cause malaria in humans are to blame for the disease’s symptoms. The female Anopheles mosquito consumes these parasites while blood-feeding, and a parasite form known as a sporozoite then migrates to the mosquito’s salivary glands and initiates a cycle of development and multiplication in the insect. (4) When the Anopheles mosquito feeds on the blood of another human. As they begin a new cycle in the liver, the sporozoites travel there next. By serving as a vector, the infected mosquito spreads the disease from one person to another. Furthermore, because the sick person transmits the parasites to the mosquito, the mosquito vector is unaffected5. Infected female Anopheles mosquitoes are a major source of mosquito bites that transmit malaria. Only Anopheles mosquitoes can spread malaria, and only after ingesting blood from a sick person. A tiny amount of blood containing microscopic malaria parasites is consumed. These parasites combine with the mosquito’s saliva and are injected into the victim around a week after the bite, during the mosquito’s subsequent blood meal. Due to the malaria parasite’s presence in an infected person’s red blood cells, malaria can also be transmitted via other means, such as sharing contaminated needles or syringes or receiving blood transfusions. Congenital malaria (transmission from a mother to her unborn child before or during delivery) is another possibility6. Malaria symptoms can be subtle, but they typically include a high fever, sweats, chills, fatigue, uncertainty, sleepiness (especially in children), feeling sick and feeling sick, stomach cramps and diarrhea, lack of appetite, muscle spasms, and yellow skin. Following a mosquito bite, these symptoms often appear 7–18 days later. However, occasionally, you may go weeks, months, or even years without having any symptoms7. A physical test and questions from the doctor about your health will be performed. In the event that your doctor has a suspicion that you may have malaria, they will perform. Blood is drawn, deposited on a glass slide, and viewed under a microscope for the test. A blood smear test can help in the diagnosis of malaria. This may help when deciding on a course of treatment. Your doctor might request more tests every 24 hours if the initial blood smear doesn’t reveal malaria. There is also a blood test that can immediately identify malaria. A blood smear is typically used to confirm the results if this quick test indicates malaria. Your doctor might do a malaria test on you if you’ve recently traveled to a location where malaria is common and get a fever up to a year later. You could require more testing to confirm that you don’t have malaria if the initial tests don’t reveal the disease. Repeated tests are conducted throughout treatment to track the progression of the infection and determine the efficacy of the therapy. In addition, the following tests may be performed: (1) PCR: Through this test, parasite nucleic acids and parasite species are identified. (2) Complete blood count: It is performed to look for signs of infection or anemia. Malaria patients can get anemia because the parasites harm red blood cells. (3) A blood glucose test: This determines the level of glucose, a specific form of sugar, in your blood8. There is a vaccination available right now to combat malaria, but travelers should not take it. In sub-Saharan Africa’s moderate-to-high-risk areas, where P. falconium infection is common, it has been licensed for use in children. Medical experts have administered more than 2.4 million doses thus far, and it has a good safety profile. The vaccine will save lives, but its effectiveness cannot be assured. In children under the age of 5, it now provides 40% protection from severe malaria after four doses, will likely save one life for every 250 children who receive the vaccine, and can reduce the risk of an episode by 50%9. The earliest possible treatment for malaria is required. Your doctor will recommend medications to get rid of the malaria parasite. Treatments for malaria are ineffective against some parasites. Combining certain medication with others is common practice. Depending on the type of parasite, you will need to take a certain treatment for a specific length of time. Artemether and artesunate are two examples of artemisinin-based antimalarial medications. If available, artemisinin combination therapy with atovaquone (Mepron) and chloroquine is the most effective treatment for P. falciparum malaria. This medicine, doxycycline (Doxy-100, Monodox, Oracea), mefloquine, quinine, and primaquine are not effective against all parasites. Malaria is treatable with medication10. Malaria can be deadly, especially if it is caused by the Plasmodium variety that is common in Africa. The most common reason for malaria deaths is one or more severe side effects, like: (1) Cerebral malaria: The brain may enlarge or suffer harm if blood cells containing parasites obstruct tiny blood arteries leading there (cerebral malaria). Comas and convulsions could result from cerebral malaria. (2) Problems breathing: If there is a buildup of fluid in your lungs, it may be difficult to breathe (pulmonary edema). (3) Malaria can damage the liver, kidneys, or even rupture the spleen, which can result in organ failure. The risk for death exists with each of these diseases. (4) Anemia: Malaria can cause a lack of red blood cells, which stops your body’s tissues from getting enough oxygen. (5) Hypoglycemia: Severe malaria and quinine, a frequent malaria therapy, both have the potential to cause low blood sugar. Extremely low blood sugar levels might cause a coma or death11. In our discussion of malaria, we covered its species, etiology, life cycle, transmission, symptoms, immunization, diagnostic procedures, treatment, and consequences. Ethical approval Not applicable. Sources of funding Not applicable. Authors’ contribution M.M.R.: conceptualization, writing − original draft preparation and supervision. M.R.I. and P.S.D.: writing and editing. All authors have reviewed and approved the final version of the manuscript before submission. Conflicts of interest disclosure The authors declare that they have no financial conflict of interest with regard to the content of this report. Research registration unique identifying number (UIN) Not applicable. Guarantor Md. Mominur Rahman.