gold standard for<unk>  diagnosis. Ring-forms and gametocytes of Plasmodium falciparum in human blood Due to the non-specific nature of<unk>  symptoms, diagnosis is typically suspected based on symptoms and travel history, then confirmed with a parasitological test. In areas where<unk>  is common, the World Health Organization (WHO) recommends clinicians suspect<unk>  in any person who reports having fevers, or who has a current temperature above 37.5 °C without any other obvious cause.<unk>  should similarly be suspected in children with signs of anemia: pale palms or a laboratory test showing hemoglobin levels below 8 grams per deciliter of blood. In areas with little to no<unk> , the WHO recommends only testing people with possible exposure to<unk>  (typically travel to a<unk> -endemic area) and unexplained fever.<unk>  is usually confirmed by the microscopic examination of blood films or by antigen-based rapid diagnostic tests (RDT). Microscopy – i.e. examining Giemsa-stained blood with a light microscope – is the gold standard for<unk>  diagnosis. Microscopists typically examine both a "thick film" of blood, allowing them to scan many blood cells in a short time, and a "thin film" of blood, allowing them to clearly see individual parasites and identify the infecting Plasmodium species. Under typical field laboratory conditions, a microscopist can detect parasites when there are at least 100 parasites per microliter of blood, which is around the lower range of symptomatic infection. Microscopic diagnosis is relatively resource intensive, requiring trained personnel, specific equipment, electricity, and a consistent supply of microscopy slides and stains. In places where microscopy is unavailable,<unk>  is diagnosed with RDTs, rapid antigen tests that detect parasite proteins in a fingerstick blood sample. A variety of RDTs are commercially available, targeting the parasite proteins histidine rich protein 2 (HRP2, detects P. falciparum only), lactate dehydrogenase, or aldolase. The HRP2 test is widely used in Africa, where P. falciparum predominates. However, since HRP2 persists in the blood for up to five weeks after an infection is treated, an HRP2 test sometimes cannot distinguish whether someone currently has<unk>  or previously had it. Additionally, some P. falciparum parasites in the Amazon region lack the HRP2 gene, complicating detection. RDTs are fast and easily deployed to places without full diagnostic laboratories. However they give considerably less information than microscopy, and sometimes vary in quality from producer to producer and lot to lot. Serological tests to detect antibodies against Plasmodium from the blood have been developed, but are not used for<unk>  diagnosis due to their relatively poor sensitivity and specificity. Highly sensitive nucleic acid amplification tests have been developed, but are not used clinically due to their relatively high cost, and poor specificity for active infections. Classification<unk>  is classified into either "severe" or "uncomplicated" by the World Health Organization (WHO). It is deemed severe when any of the following criteria are present, otherwise it is considered uncomplicated. * Decreased consciousness * Significant weakness such that the person is unable to walk * Inability to feed * Two or more convulsions * Low blood pressure (less than 70 mmHg in adults and 50 mmHg in children) * Breathing problems * Circulatory shock * Kidney failure or haemoglobin in the urine * Bleeding problems, or hemoglobin less than 50 g/L (5 g/dL) * Pulmonary oedema * Blood glucose less than 2.2 mmol/L (40 mg/dL) * Acidosis or lactate levels of greater than 5 mmol/L * A parasite level in the blood of greater than 100,000 per microlitre (μL) in low-intensity transmission areas, or 250,000 per μL in high-intensity transmission areas Cerebral<unk>  is defined as a severe P. falciparum-malaria presenting with neurological symptoms, including coma (with a Glasgow coma scale less than 11, or a Blantyre coma scale less than 3), or with a coma that lasts longer than 30 minutes after a seizure.
Malaria
Zika fever
Chikungunya
Leptospirosis
Airport malaria
Lassa fever
Brain fever
Dengue fever