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Rickettsial infections are caused by bacteria from the Rickettsia genus which are often spread by biting ticks, fleas, mites or lice. Rickettsia can cause mild to severe illness and Rickettsia species can be found worldwide. Early stage, nonspecific symptoms of infections can make clinical diagnosis difficult. Rickettsial infection symptoms, if present, typically develop within 1 -2 weeks of exposure and include fever, headache, malaise, rash, nausea, and vomiting.

The simultaneous concentration and recovery of microbes in drinking water is important for responding to potential water-related events such as pathogen contamination or bioterrorism and could be a cost-effective technique for routine monitoring of drinking water quality. Scientists at the CDC have combined two techniques, ultrafiltration (UF) and insulator-based dielectrophoresis (iDEP) in series, to achieve significant concentration of microbes and pathogens for analysis.

Transduced human cell lines expressing high levels of native HIV-1 Envelope on their surface membrane, in the unmodified or interdomain stabilized form. These cell lines provide a stable source of native HIV-1 envelope for multiple uses, including the high-efficiency production of virus-like particles (VLPs) for use as vaccines, testing new inhibitors or neutralizing antibodies, or identifying/capturing B cells that produce broadly neutralizing antibodies from infected/vaccinated humans or animals.

Scrub typhus is a bacterial disease caused by Orientia tsutsugamushi (O. tsutsugamushi or Ots) that is spread to people through bites of infected chiggers (larval mites). The most common symptoms can include fever, headache, body aches, and sometimes rash. Severe illness can lead to organ failure and bleeding which can be fatal if left untreated. Most cases of scrub typhus occur in Asia Pacific countries, however, recent reports document establishment in the Arabian Peninsula, Chile, and possibly Kenya.

Scientists at NIAID have developed broadly neutralizing antibodies (bNAbs) with enhanced neutralizing activity against HIV-1. Specifically, previously unknown gp120 interactions with a newly elucidated quaternary receptor (CD4)-binding site in the HIV-1 envelope have been discovered by engrafting the extended heavy-chain framework region 3 (FR3) loop of VRC03 onto several potent bNAbs (including VRC01, VRC07 and N6).

CDC researchers have developed a patented set of RT-PCR and sequencing primers based on HIV-1 group M sequences. Evaluation of the primers using samples collected around the world demonstrated broad detection capacity for multiple HIV-1 group subtypes and predominant circulating recombinant forms. Commercially available HIV-1 drug resistance (HIVDR) genotyping assays are expensive and have limited ability to detect non-B subtypes. This optimized assay is broadly sensitive in genotyping HIV-1 group M viral strains and more sensitive than other assays in detecting mixed viral populations.

The U.S. Food and Drug Administration and World Health Organization (WHO) approved the antiretroviral drug emtricitabine (FTC)/ tenofovir disoproxil fumurate (TDF) combination for HIV pre-exposure prophylaxis (PrEP) in high risk populations. Efficacy of PrEP depends strongly on adherence to taking the FTC/TDF pill daily. In the US, the Centers for Disease Control and Prevention (CDC) estimates that 1.2 million Americans will benefit from PrEP. FTC is also a key component of antiretroviral therapy (ART) regimens of HIV-infected persons and significantly associated with adherence.

Zika virus infection during pregnancy can cause microcephaly and other severe birth defects. The CDC Zika MAC-ELISA (IgM antibody capture enzyme-linked immunosorbent assay) currently used for diagnosis detects antibodies produced to fight a Zika virus infection. However, reactivity of flavivirus antibodies (from exposure to other mosquito-borne infections such as dengue or West Nile virus) can complicate the interpretation of these results.

Formation of biofilms (microorganisms) on medical devices is a common cause of infection and device replacement. For example, biofilm formation on urinary catheters is associated with the development of catheter-associated urinary tract infections (CAUTI), and recent studies indicate that approximately 9% of HAIs stem from CAUTI. Urinary catheters are also thought to be one of the largest reservoirs of nosocomial antibiotic-resistant pathogens. The related increases in patient morbidity, mortality, and costs with CAUTI are substantial.

According to 2010-2014 World Health Organization (WHO) research, dog-transmitted human rabies was present or suspected in 150 countries and territories worldwide. Domestic dogs were the most common reservoir of the rabies virus in these countries, and more than 99% of human deaths were caused by dog-transmitted rabies. Rabies is 100% preventable in dogs with appropriate administration of vaccines.