Malaria in Ethiopia.

Between 1 January and 20 October 2024 more than 7.4 million cases of Malaria were reported in Ethiopia, with 1157 deaths recorded, a case fatality rate of 0.02%, according to a press release issued by the World Health Organization on 31 October 2024. On these infections, 95% were causes by Plasmodium falciparum. This is the highest number of cases reported in Ethiopia in seven years, and part of an ongoing rising trend of Plasmodium falciparum infections; in 2023, 4.21 million Malaria infections, with 527 deaths, with 70% caused by Plasmodium falciparum.

The overwhelming majority of cases occurred in the west of the country, with four regions accounting for 81% of all recorded infections and 89% of known deaths, with 44% of cases and 667 deaths in Oromo, 18% of cases and 56 deaths in Amhara, 12% of cases and 250 deaths in Southwest Ethiopia, and 7% of cases and 45 deaths in South Ethiopia. 

Geographical distribution of Malaria cases as of 20 October 2024. World Health Organization.

Of Ethiopia's 523 worodas (districts), 222 have been identified as having a high Malaria burden, together accounting for 75% of recorded Malaria cases in 2023. Fifty of these high-burden worodas are considered to be hard-to-access due to ongoing conflicts.

A slight majority of cases are males, who accounted for 56% of cases treated as outpatients and 52% of inpatient admissions. Children accounted for 16% of outpatients and 25% of inpatient admissions. This age and sex distribution is thought to be due to patterns of seasonal migration, with large numbers of adult male migrant workers seeking work in high-risk areas during the peak of the Malaria season. 

From 2000-onwards, Ethiopia had a steady reduction in the number of Malaria cases each year, driven by improved surveillance, roll-out of malaria interventions, and community health extension program. The number of cases fell to an all-time low in 2019, when only 900 000 cases were recorded, and there was no wide-ranging major epidemic, only sporadic local outbreaks. However, the country began to suffer a resurgence of the disease from 2021 onwards, with 1.3 million cases in 2021, 3.3 million cases in 2022, and 4.1 million cases in 2023. This return appears to have been driven by the Plasmodium falciparum strain of the disease, which caused 70% of the infections in 2023, and which appears to have become endemic in areas where it was not previously known.

Weekly trend of malaria cases in Ethiopia, 01 January 2021 to 13 October 2024. World Health Organization.

Malaria is caused by parasitic unicellular Eukaryotes of the genus Plasmodium, and affects a wide range of terrestrial Vertebrates. Five different species of Plasmodium can cause Malaria in Humans, with most infections caused by either Plasmodium falciparum or Plasmodium vivax, both of which are endemic to Ethiopia. The parasites are primarily spread via the bite of the female Anopheles Mosquitoes (males do not bite), but can also be spread through blood transfusions, organ transplants, or practices such as needle-sharing.

Photomicrograph of a blood smear containing a macro- and microgametocyte of the Plasmodium falciparum parasite. Both macro- and microgametocytes are products of the erythrocytic life cycle. Within a few minutes after the Anopheles sp. vector ingests the gametocytes, microgametocytes develop into microgametes, which are able to fertilize gametes. Centers for Disease Control and Prevention/Wikipedia Commons.

Malaria manifests with approximately 10-15 days after infection, as a fever, headache, and chills. Mild cases often pass soon, and can be difficult to identify as Malaria, however, more severe cases can be fatal in as little as 24 hours after the onset of symptoms. 

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Zorotypus komatsui: A new species of Ground Louse from Cameroon.

Ground Lice, Zoraptera, are small (less than 3 mm) Insects typically found under bark. They are one of the smallest orders of Insects, with only 46 described species, although this may be a severe underestimation of their true diversity, as they are both easily overlooked and morphologically conservative. Ground Lice have a fossil record dating back to the Palaeozoic, with the last common ancestor of all living species thought to have lived about 270 million years ago. They are mostly wingless, and were once thought to be so throughout their life-cycle (the name Zoraptera means 'pure wingless') but winged forms are produced at some times of year, helping them colonise new areas.

In a paper published in the journal ZooKeys on 1 September 2023, Yoko Matsumura of the Department of Ecology and Systematics at Hokkaido University, Munetoshi Maruyama of the Kyushu University Museum, Nelson Ntonifor of the Department of Agronomic and Applied Molecular Sciences at the University of Buea, and Rolf Beutel of the Entomology Group at Friedrich-Schiller-Universität Jena, describe a new species of Ground Louse from Cameroon.

The new species is described from a single wingless male specimen discovered under a 30 cm long rock half embedded in soil close to the village of Nyasoso in Southwest Region, Cameroon, by Takashi Komatsu and Munetoshi Maruyama. A subsequent search of the surrounding forest yielded no further specimens. It is placed in the genus Zorotypus, and given the specific name komatsui; no explanation is given for this name, but it presumably honours Takashi Komatsu. The single known specimen of Zorotypus komatsui is a wingless male, 2.42 mm in length, with a head 0.47 mm long and 0.50 mm wide. It is light brown in colour, lacking any markings, even eye spots. 

Digitalmicroscopic images of the holotype of Zorotypus komatsui (ventral view) (A) habitus, (B) head and prothorax, (C) hindleg and abdomen. Matsumura et al. (2023).

Matsumura et al. also report the presence of Zorotypus vinsoni, a species previously known only from Mauritius, on Madagascar. This is the second species found to be present on both islands, following Zorotypus delamarei, which was discovered initially on Madagascar and subsequently on Mauritius. Mauritius was formed by volcanic activity about 8.9 million years ago, and probably largely resurfaced by another volcanic episode about 1 million years ago. This being the case, it is likely that both species of Zorotypus found on Mauritius have colonised the island from Madagascar in the recent past.

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