Protecting yourself from mosquito bites is necessary as it lessen the chances of contracting many mosquito borne diseases, such as malaria, dengue, West Nile virus and yellow fever. Many commercial mosquito repellants contains DEET, which should be used with caution as many studies have found DEET to have harmful effects. Chemical repellents have some success in repelling mosquitoes, but not because mosquitoes don’t like the smell of these repellents. Rather, it’s because these repellents are effective at masking the smell of carbon dioxide and lactic acid.