Malawi is one of the safest African countries for travellers, but you should still be reasonably cautious and employ common sense.
Robberies, pickpocketing and violent muggings do occur. However, these are still rare compared with their incidence in other countries, and violence is not the norm.
Potential dangers at Lake Malawi include encountering a hippo or crocodile after dusk, when they come up onto beaches. The Shire River is replete with crocodiles, and locals disappear in dugouts on a regular basis, so be careful of dipping your hand in the water while on a river safari. Popular tourist beaches are safe, although, just to be sure, you should seek local advice before diving in. Avoid sheltered, reedy beaches where bilharzia host snails are found. The most dangerous animals in Malawi are the mosquitoes that transmit malaria.
Some government websites offer travel advisories and information on current hot spots.
Australian Department of Foreign Affairs (www.smartraveller.gov.au)
British Foreign Office (www.fco.gov.uk)
German Federal Foreign Office (www.auswaertiges-amt.de)
Global Affairs Canada (www.voyage.gc.ca)
Japanese Ministry of Foreign Affairs (www.mofa.go.jp)
Netherlands Ministry of Foreign Affairs (www.government.nl)
New Zealand Ministry of Foreign Affairs (www.safetravel.govt.nz)
US State Department (www.travel.state.gov)