I previously wrote about the regular periodicity of colony collapse events due to Thai Sacbrood in Asia. Such periodic virus epidemics are common in human, animal, and plant populations (Fig. 2). The same goes for insect populations. Dr. Jennifer Cory (2005) gives an example in the case of the Western Tent Caterpillar, whose population collapses every 6-11 years due to a virus. She also notes that sublethal effects of the virus appear to regulate the caterpillar population—that is, the virus does not need to necessarily kill the host to affect it at the population level . She also brings up a point of interest to beekeepers: “that the diversity of the virus population plays a role in infection severity, such that mixed genotype infections are more virulent than any individual clone.” As we beekeepers bring large numbers of colonies together, we ensure that multiple genotypes of each virus strain have more chances to interact. I’ll return to this point when I discuss how beekeepers help to create virus epidemics.
A good immune response is reliant on the reaction of an immunogenic agent and a fully competent immune system. Immunogenicity of the vaccine antigen will be reduced by poor storage or inappropriate administration. Immunocompetence of the animal may be compromised by a variety of factors including poor health, nutritional status, genetic factors, concurrent drug therapy and stress. Under certain conditions, for example extreme disease pressure and variant challenge, fully immune birds may succumb to disease. Therefore, successful vaccination may not be synonymous with full protection in the face of a disease challenge.
This guideline addresses several issues in the management of acute bacterial rhinosinusitis (ABRS), including (1) inability of existing clinical criteria to accurately differentiate bacterial from viral acute rhinosinusitis, leading to excessive and inappropriate antimicrobial therapy; (2) gaps in knowledge and quality evidence regarding empiric antimicrobial therapy for ABRS due to imprecise patient selection criteria; (3) changing prevalence and antimicrobial susceptibility profiles of bacterial isolates associated with ABRS; and (4) impact of the use of conjugated vaccines for Streptococcus pneumoniae on the emergence of non-vaccine serotypes associated with ABRS. Full text*Every 12 to 18 months following publication, IDSA reviews its guidelines to determine whether an update is required. This guideline was last reviewed and deemed current as of 05/2015.