Yellow fever other feverish illnesses such as malaria. Other viral hemorrhagic fevers, such as Ebola virus, Lassa virus, Marburg virus, and Junin virus, must be excluded as the cause. Personal prevention of yellow fever includes vaccination and avoidance of mosquito bites in areas where yellow fever is endemic. Institutional measures for prevention of yellow fever include vaccination programmes and measures of controlling mosquitoes. Programmes for distribution of mosquito nets for use in homes are providing reductions in cases of both malaria and yellow fever. Use of EPA-registered insect repellent is recommended when outdoors. Exposure for even a short time is enough for
SMS Hessen "Hessen" was tasked with clearing paths for merchant vessels in the iced-over Baltic. She also made visits to the ports of Libau, Latvia, and Reval, Estonia, during this period. The ship joined the pre-dreadnought , the flagship of "VAdm" Konrad Mommsen, for a trip to Spain that lasted from 12 May to 19 June. During the cruise, "Hessen" visited the Canary Islands and Cape Verde in the central Atlantic. In July, "Hessen" and the torpedo boat "T190" visited Neufahrwasser; they were the first German warships to visit Danzig since Germany lost control of the city to Poland after the war.