There are 34 countries in Africa where life expectancy at birth of both men and women is equal to or less than 51.
Data are from the 2003 UN estimates.
Note that life expectancy at birth is strongly impacted by infant mortality.
Name of country Av. Age of Men Av. Age of Women Angola 39 41 Benin 48 51 Botswana 39 40 Burkina Faso 45 46 Burundi 40 41 Cameroon 45 47 Central African 38 40 Republic Chad 44 46 Rep of Congo 47 50 DR Congo 41 43 Djibouti 45 47 Equatorial 48 50 Guinea Ethiopia 45 46 Guinea 49 49 Guinea Bissau 44 47 Ivory Coast 41 41 Kenya 43 46 Lesotho 32 38 Liberia 41 42 Malawi 37 38 Mali 48 49 Mozambique 37 40 Namibia 43 46 Niger 46 46 Rwanda 39 40 Sierra Leone 33 35 Somalia 45 48 South Africa 45 51 Swaziland 33 35 Tanzania 42 44 Togo 48 51 Uganda 45 47 Zambia 33 32 Zimbabwe 34 33