Whether these fluctuations are enough to translate into reduced Lyme cases is a complex question. Tick surveying involves collecting ticks from the field of from host animals and testing them for B. burgdorferi infection. Serosurveys involve testing a given human population for anti- Borrelia antibodies. But, one must remember that it was not shown whether these spirochetes were viable or not. In addition, this data does not lend any evidence as to the competence of these insects as vectors of the Lyme spirochete.
Competence means the ability of a vector to acquire, maintain, and transmit a particular pathogen.
To this end, Magnarelli and colleagues tried to infect hamsters by subjecting them to B. burgdorferi -infected mosquitoes. No spirochetes were isolated from the hamsters, but one animal did produce antibodies to the spirochete, suggesting a transient infection. To complicate matters, different species of mosquitoes feed off of different hosts. If the mosquito is vector competent, in order to qualify as a vector of B. burgdorferi to people, the mosquito must be able to feed on mice and humans. Not all species of mosquito were infected.