Malaria

Malaria

ntangakeneth.blogspot.com

Definition

Malaria is one of the major public health problems of the country. Around 1.5 million confirmed cases are reported annually by the National Vector Borne Disease Control Programme (NVBDCP), of which 40–50% is due to Plasmodium falciparum. Malaria is curable if effective treatment is started early. Delay in treatment may lead to serious consequences including death. Prompt and effective treatment is also important for controlling the transmission of malaria.

Epidemiology

• 2 billion people live in areas at risk of malaria transmission in 106 countries and territories.
• The World Health Organization estimates that in 2016 malaria caused 216 million clinical episodes and 445,000 deaths.

Types

Parasites of the genus Plasmodium cause malaria. Although there are many species of Plasmodium, only five infect humans and cause malaria.

P. falciparum: Found in tropical and subtropical areas; major contributor to deaths from severe malaria

P. vivax: Found in Asia and Latin America; has a dormant stage that can cause relapses

P. ovale: Found in Africa and the Pacific islands

P. malariae: Worldwide; can cause a chronic infection

P. knowlesi: Found throughout Southeast Asia; can rapidly progress from an uncomplicated case to a severe malaria infection

Parasite life cycle

The life cycle of the falciparum malaria parasite is complex. When an infectious mosquito feeds on a human being, parasites (called sporozoites) are injected into the bloodstream. From here they travel directly to the liver where they mature for about 6 days. At this stage, there are no symptoms of disease in the person who has been infected.

The life cycle of the malarial parasite

Infections begin when the following stages occur:

1. Sporozoites, the infective stages, are injected by a mosquito and are carried around the body until they invade liver hepatocytes.
2. Then it undergoes a phase of asexual multiplication (exoerythrocytic schizogony) resulting in the production of many uninucleate merozoites. These merozoites flood out into the blood and invade red blood cells.
3. They initiate the second phase of asexual multiplication (erythrocytic schizogony) resulting in the production of about 8-16 merozoites which invade new red blood cells.
4. The infection progresses, some young merozoites develop into male and female gametocytes that circulate in the peripheral blood until they are taken up by a female anopheline mosquito when it feeds.
5. Within the mosquito the gametocytes mature into male and female gametes, fertilization occurs and a motile zygote (ookinete) is formed within the lumen of the mosquito gut, the beginning of a process known as sporogony. The ookinete penetrates the gut wall and becomes conspicuous oocyst within which another phase of multiplication occurs resulting in the formation of sporozoites that migrate to the salivary glands of a mosquito and are injected when the mosquito feeds on a new host.

Risk factors

• Rain and increased water bodies are appropriate for mosquito breeding and disease transmission.
• Young children and infants.
• Pregnant women.
• People with weak immunity are more susceptible to the risk of malaria.
• People traveling to malaria-infected areas.
• Poverty and lack of health awareness and education contribute to spreading the disease and increasing mortality rate around the world.

Causes

Malaria can occur if a mosquito infected with the Plasmodium parasite bites you. There are four kinds of malaria parasites that can infect humans: Plasmodium vivax, P. ovale, P. malariae, and P. falciparum. P. falciparum causes a more severe form of the disease and those who contract this form of malaria have a higher risk of death. An infected mother can also pass the disease to her baby at birth. This is known as congenital malaria. Malaria is transmitted by blood, so it can also be transmitted through:

• An organ transplant
• A transfusion
• Use of shared needles or syringes

Symptoms

A malaria infection is generally characterized by recurrent attacks with the following signs and symptoms:

• Headache
• Fever
• Shivering
• Joint pain
• Vomiting
• Hemolytic anemia
• Jaundice
• Hemoglobin in the urine
• Retinal damage
• Convulsions
• Coma
• Bloody stools
• Abdominal pain
• Shaking chills that can range from moderate to severe
• High fever
• Profuse sweating

Complications

• Malaria is a serious illness that can be fatal if not diagnosed and treated quickly. Pregnant women, babies, young children and the elderly are, particularly at risk.
• The Plasmodium falciparum parasite causes the most severe malaria symptoms and most deaths.
• As complications of severe malaria can occur within hours or days of the first symptoms, it’s important to seek urgent medical help as soon as possible.

Other complications that can arise as a result of severe malaria include:

• liver failure and jaundice – yellowing of the skin and whites of the eyes
• shock – a sudden drop in blood pressure
• pulmonary edema – a build-up of fluid in the lungs
• acute respiratory distress syndrome (ARDS)
• abnormally low blood sugar – hypoglycemia
• kidney failure
• swelling and rupturing of the spleen
• dehydration

Diagnosis and test

Blood tests can show the presence of the parasite and help tailor treatment by determining:

• Whether you have malaria
• Which type of malaria parasite is causing your symptoms
• If your infection is caused by a parasite resistant to certain drugs
• Whether the disease is affecting any of your vital organs

Some blood tests can take several days to complete, while others can produce results in less than 15 minutes.

Blood test

Treatment and medications

Besides supportive care, the medical team needs to decide on the appropriate antibiotics to treat malaria. The choice will depend on several factors, including

• The specific species of parasite identified,
• The severity of symptoms, and
• Determination of drug resistance based on the geographic area where the patient traveled.

Physicians will administer the medication in pill form or as an intravenous antibiotic depending on above factors.

The most commonly used medications are

• Chloroquine (Aralen),
• Doxycycline (Vibramycin, Oracea, Adoxa, Atridox),
• Quinine (Qualaquin),
• Mefloquine (Lariam),
• Atovaquone/proguanil (Malarone),
• Artemether/lumefantrine (Coartem), and
• Primaquine phosphate (Primaquine).

Prevention

• Use mosquito repellents regularly – apply it to your skin, especially to all exposed areas, and clothing. For your skin, opt for a repellent that contains at least a 10 percent concentration of DEET.
• Use camphor as a repellent- you can light camphor in the room with all the doors and windows closed. Leave it for about 15-20 minutes to keep the mosquitoes away. You can also use the lemon and clove technique- just stick some cloves in a half-sliced lemon and keep it near your bed while you sleep.
• Use a mosquito bed net while sleeping.
• Wear long-sleeved shirts, pants, and socks.
• Wear covered shoes when outside.
• Avoid exercising outdoors as mosquitoes get attracted to sweat.
• Empty and clean all containers that hold water such as flower pots, flower vases, and animal dishes – at least once a weak – to prevent mosquitoes from breeding at your house.
• Keep your surroundings clean, ensuring that there is no stagnant water, which is a breeding ground for the mosquitoes?
• Try to stay in air-conditioned or well-screened housing.