Effects of Seasonal Conditions on Abundance of Malaria Vector Anopheles stephensi Mosquitoes, Djibouti, 2018-2021.

We describe the influence of seasonal meteorologic variations and rainfall events on Anopheles stephensi mosquito populations during a 40-month surveillance study at a US military base in Djibouti. Focusing surveillance and risk mitigation for An. stephensi mosquitoes when climatic conditions are optimal presents an opportunity for malaria prevention and control in eastern Africa.

Infectivity of Metarhizium anisopliae (Hypocreales: Clavicipitaceae) to Phlebotomus papatasi (Diptera: Psychodidae) under laboratory conditions.

Susceptibility of Phlebotomus papatasi Scopoli (Diptera: Psychodidae) larvae to the entomopathogenic fungus Metarhizium anisopliae (Metschinkoff) Sorokin (Ma79) (Hypocreales: Clavicipitaceae) was evaluated at two different temperatures. The ability of the fungus to reinfect healthy sand flies was followed up for approximately 20 wk and the effect of in vivo repassage on the enhancement of its virulence was assessed. The fungus reduced the adult emergence at 26 +/- 1 degrees C when applied to larval diet. Six spore concentrations were used in the bioassays ranging from 1 x 10(6) to 5 x 10(8) spores/ml. Mortality decreased significantly when the temperature was raised to 31 +/- 1 degrees C at all tested concentrations. Fungus-treated vials were assayed against sand fly larvae at different time lapses without additional reapplication of the fungus in the media to determine whether the level of inocula persisting in the media was sufficient to reinfect healthy sand flies. Twenty weeks postapplication, there were still enough infectious propagules of Ma79 to infect 40% of P. papatasi larvae. A comparison between the infectivity of 10 subsequent in vitro cultures and the host-passed inocula of the fungus against sand fly larvae was conducted. Mortalities of P. papatasi larvae changed significantly when exposed to inocula passed through different insects. Presented data can provide vector control decision makers and end users with fundamental information for the introduction and application of M. anisopliae as an effective control agent against the main cutaneous leishmaniasis old-world vector P. papatasi.

Crimean-Congo hemorrhagic fever, Afghanistan, 2009.

In response to an outbreak of Crimean-Congo hemorrhagic fever in western Afghanistan, we measured immunoglobulin G seroprevalence among household members and their animals. Seroprevalence was 11.2% and 75.0% in humans (n = 330) and livestock (n = 132), respectively. Persons with frequent exposure to cattle had an elevated risk of being immunoglobulin G positive.

Sticky bottle traps: a simple and effective method for collecting adult phlebotomine sand flies from rodent burrows in a Leishmania-endemic region of Egypt.

We describe a simple, economic, and effective method for constructing sticky bottle traps that can be used to capture adult sand flies from rodent burrows. Although sand fly surveillance activities often employ light- or CO2-baited traps, sticky papers secured to a post or placed on the ground can also be used. However, in arid environments, sand and other debris often collect on the sticky surface, reducing trap effectiveness, capacity, and a means for rapid discrimination and enumeration of adult specimens. Herein, a procedure for constructing sticky bottle traps is provided, as well as preliminary results from a recent sand fly field survey utilizing this device.

Evidence of Rickettsia and Orientia Infections Among Abattoir Workers in Djibouti.

Of 49 workers at a Djiboutian abattoir, eight (16%, 95% confidence interval [CI]: 9-29) were seropositive against spotted fever group rickettsiae (SFGR), two (4%, 95% CI: 1-14) against typhus group rickettsiae, and three (6%, 95% CI: 2-17) against orientiae. One worker (9%, 95% CI: 2-38) seroconverted against orientiae during the study period. This is the first evidence of orientiae exposure in the Horn of Africa. SFGR were also identified by polymerase chain reaction in 32 of 189 (11%, 95% CI: 8-15) tick pools from 26 of 72 (36%) cattle. Twenty-five (8%, 95% CI: 6-12) tick pools were positive for Rickettsia africae, the causative agent of African tick-bite fever. Health-care providers in Djibouti should be aware of the possibility of rickettsiae infections among patients, although further research is needed to determine the impact of these infections in the country.

Crimean Congo Hemorrhagic Fever Virus and Alkhurma (Alkhumra) Virus in Ticks in Djibouti.

Crimean Congo hemorrhagic fever virus and Alkhumra virus, not previously reported in Djibouti, were detected among 141 (infection rate = 15.7 per 100, 95% CI: 13.4-18.1) tick pools from 81 (37%) cattle and 2 (infection rate = 0.2 per 100, 95% CI: 0.0-0.7) tick pools from 2 (1%) cattle, respectively, collected at an abattoir in 2010 and 2011.

Complete Genome Sequence of Chikungunya Virus Isolated from an Aedes aegypti Mosquito during an Outbreak in Yemen, 2011.

Chikungunya virus is recognized as a serious public health problem. The complete genome was sequenced for a chikungunya virus isolated from the mosquito Aedes aegypti during a 2011 outbreak in Al Hodayda, Yemen, which resulted in significant human fatalities. Phylogenetic analysis demonstrated that this Yemeni isolate is most closely related to Indian Ocean strains of the east/central/south African genotype.

Chikungunya outbreak in Al-Hudaydah, Yemen, 2011: epidemiological characterization and key lessons learned for early detection and control.

Little is known about the occurrence of chikungunya fever in the Eastern Mediterranean Region of the World Health Organization (WHO). In January 2011, the Ministry of Public Health and Population (MoPH&P) of Yemen reported to WHO an increasing number of "dengue-like" acute febrile illnesses of unknown origin from one of its coastal governorates. An epidemiological investigation was conducted in Al-Hudaydah governorate between 23 and 26 January 2011 by a joint team of WHO, the MoPH&P of Yemen and the U.S. Naval Medical Research Unit (NAMRU-3) in Cairo, Egypt. The investigation led to the detection of an outbreak of chikungunya in Yemen which was the first time ever from any of the 22 countries in the Eastern Mediterranean Region of WHO. Appropriate public health control measures were strengthened following the investigation, and the outbreak was contained. This paper provides a short description of the outbreak and its epidemiological characteristics and highlights the important lessons that were learned for early detection and control of chikungunya in countries where competent vectors for transmission of the virus exist.

Seasonal abundance, number of annual generations, and effect of an entomopathogenic fungus on Phlebotomus papatasi (Diptera: Psychodidae).

The monthly density of the sand fly, Phlebotomus Papatasi Scopoli (Diptera: Psychodidae), was monitored during 2009 at Burg El-Arab, a rural district located close to the Mediterranean coast of Egypt. The number of annual generations and the efficacy of microbial control by the entomopathogenic fungus, Metrahizium anisopliae (Metsch.) Sorok (Ma79), were determined in the laboratory under atmospheric conditions, simulating those of the animal shelters in the study area. We used two collecting techniques; CDC light traps and oiled paper traps, to quantify sand fly density inside houses and in the open field. Adult flies exhibited a seasonal range from April to December. The seasonal pattern was bimodal, with one peak in July and the second one in October. Calculations of the correlation coefficient (r) revealed a significant role of temperature and relative humidity in the monthly abundance of the sand flies in the study area. P. papatasi colony completed seven annual generations under semifield conditions, but the mean developmental time of each immature stage and the mean total duration of development from egg to adult for each generation varied according to the prevailing temperature. The longest generation time was observed in winter (the mean ± SD was 118 ± 11.70 d), and the shortest one occurred at the highest temperatures in summer (the mean ± SD was 25.21 ± 2.04 d). In microbial control studies, the entomopathogenic fungus, M. anisopliae, was used at 15 × 10(8) spores/g food as a standard dose against the second-instar larvae of P. papatasi at the different seasons during 2009. Mortality reached 100% in winter and decreased to 56.0% as the prevailing temperature increased during the summer season.

Detection of Chikungunya virus in Aedes aegypti during 2011 outbreak in Al Hodayda, Yemen.

In October 2010, the Ministry of Public Health and Population reported an outbreak of dengue-like acute febrile illness in Al Hodayda governorate. By January 2011, a total of 1542 cases had been recorded from 19 of the 26 districts in the governorate with 104 purportedly associated deaths. In response this event, in January 2011 entomological investigations aimed at identifying the primary vector and the epidemic associated etiological agent were carried out. Based on the reported cases and the progress of the outbreak in the governorate, mosquito collection was undertaken in two of the most recent outbreak areas; Al Khokha district (130km south of Al Hodayda) and Al Muneera district (100km north). Mosquito adults were collected from houses using BG-sentinel™ traps, aspiration of resting mosquitoes and knock-down spraying. Indoor and outdoor containers adjacent to the houses were inspected for larvae. Subsequently mosquito pools were analyzed by RT-PCR for detection of the four dengue virus serotypes (DENV-1, DENV-2, DENV-3, DENV-4), and for Chikungunya virus (CHIKV). Aedes aegypti was the dominant mosquito species collected. Four pools represent 40% of the tested pools, all containing adult female Ae. aegypti, were positive for CHIKV. Three CHIKV isolates were obtained from the RNA positive mosquito pools and identified by rRT-PCR. This finding marks the first record of CHIKV isolated from Ae. aegypti in Yemen. The larval container and Breteau indices in the visited localities surveyed were estimated at 53.8 and 100, respectively. The emergence of this unprecedented CHIKV epidemic in Al Hodayda is adding up another arboviral burden to the already existing vector-borne diseases. Considering the governorate as one focal port in the Red Sea region, the spread of the disease to other areas in Yemen and in neighboring countries is anticipated. Public health education and simple measures to detect and prevent mosquito breeding in water storage containers could prevent and reduce the spread of mosquito-borne viruses like CHIKV and DENV in Yemen.

Pathogenicity of two entomopathogenic hyphomycetes, Beauveria bassiana and Metarhizium anisopliae, to the housefly Musca domestica L.

The pathogenicity of three isolates of Metarhizium anisopliae and two isolates Beauveria bassiana originating from different insect species and localities was tested against housefly larvae. Only one isolate of M. anisopliae (Ma23) and the two isolates of B. bassiana (Bb2, Bb108) significantly (P<0.05) reduced the percentage of emerging adults. At the highest tested concentration 10(7) spores/ml. the reduction in the percentage of adult emergence was 93.8%. 61.3% and 49% for Bb2. Ma23 and Bb108. respectively. Based on the IC50 values Bb2 was the most virulent isolate followed by Ma23 and Bb108, (1.13. 1.7 and 4 x 10(6). respectively). The ability of adult flies to pick up conidiospores from contaminated media as well as the possibility of isolate recycling through cadavers of fungus-killed adults were also investigated. Adults were able to pick up conidiospores from the contaminated media. All contaminated adult cadavers subsequently sporulated when placed under high relative humidity conditions. When adult flies were exposed to mycotised cadavers 12. 75 and 76% of the adults exposed to Bb2, Ma23 and Bb108, respectively sporulated under high relative humidity conditions.

Enzymatic changes and cytotoxic effects of Metarhizium anisopliae fungal extracts on the Egyptian cotton leaf worm Spodoptera littoralis (SL 96) cell line.

The extra-and intra-cellular extracts of two Metarhizium anisopliae isolates: Ma23 and MR3, were introduced to a cell line of Spodoptera littoralis. The cell line (Sl96) was established in the Entomovirology centre from S. littoralis ovaries. MR3 extracellular fluid-treated culture had an increase in the Acid phosphatase (AcP) level as compared either to the untreated cell line or to the fungal extract alone. Moreover, the enzymatic tests showed that alpha and beta-glucosidases have been detected only after the treatment with extracellular fluid of MR3. The elevation of AcP level that appeared after the treatment of MR3 coincided with a conspicuous decrease of about one third of the initial number (96 x 10(3)) of the Sl96 cell. vacuolization and lysis of some cells. Deformation of the cells and shrinkage of cell membrane have been observed in the case of Ma23 treatments. Crystal formation was restricted to the treatment of MR3 extracellular extract. The results are discussed in the light of the possibility that the cytotoxic effects and enzymatic changes are attributed to the virulence of the fungal isolates.