In the Journals: MERS and . . . Camels?

In the mid-1950s, 27 companies made vaccines. By the early 1980s — largely due to merger and drop out — only 18 companies made them. Today, four major pharmaceutical companies make vaccines for America’s children. One reason is that, compared with drugs, vaccines aren’t particularly lucrative. Also, the business model for vaccines is that if they aren’t sold in wealthy, developed world nations like the United States, then they are unlikely to be profitable. So what about diseases that kill people in developing world countries like Ebola, SARS, MERS-CoV and chikungunya? Who will be making vaccines to prevent these diseases?

One interesting approach concerns the coronavirus that causes Middle East Respiratory Syndrome otherwise known as MERS-CoV. During the past few years several outbreaks of MERS-CoV have occurred in the Middle East and in South Korea, each with an estimated mortality rate of 35 percent. While it is unlikely that we will see a vaccine to prevent MERS-CoV in the near future, we still might be able to prevent the disease. How? By attacking the disease reservoir: dromedary camels.

Recently, research teams from the Netherlands, Germany and Spain collaborated to make a MERS-CoV vaccine for camels. Scientists took the gene that codes for the MERS-CoV spike protein (the protein on the virus that attaches to cells) and cloned it into a weakened form of the modern smallpox vaccine called Modified Vaccinia Ankara. Then they took this recombinant vaccine virus and inoculated camels both intranasally and intramuscularly, finding that animals that were inoculated excreted significantly less infectious virus when challenged intranasally with MERS-CoV than those that weren’t inoculated (Haagmans BL, van den Brand JM, Raj S, et al. An orthopoxvirus-based vaccine reduces virus excretion after MERS-CoV infection in dromedary camels. Science. 2016 Jan. 1;351(6268):77-81. Kupferschmidt K. “Camel Vaccine Offers Hope to Stop MERS.” Science. 2015 Dec 18;350(6267):1453).

Time will tell. But it is certainly hopeful that one could largely reduce the incidence of MERS-CoV by attacking the animal reservoir of the virus. In essence, the exact same strategy that is used to try and lessen the incidence of rabies.