Centers for Disease Control and Prevention

About: Centers for Disease Control and Prevention is a government organization based out in Atlanta, Georgia, United States. It is known for research contribution in the topics: Population & Public health. The organization has 58238 authors who have published 82592 publications receiving 4405701 citations. The organization is also known as: CDC & Centers for Disease Control and Prevention (CDC).

An interferon-γ-related cytokine storm in SARS patients

Abstract: Fourteen cytokines or chemokines were analyzed on 88 RT-PCR-confirmed severe acute respiratory syndrome (SARS) patients. IFN-gamma, IL-18, TGF-beta, IL-6, IP-10, MCP-1, MIG, and IL-8, but not of TNF-alpha, IL-2, IL-4, IL-10, IL-13, or TNFRI, were highly elevated in the acute phase sera of Taiwan SARS patients. IFN-gamma was significantly higher in the Ab(+) group than in the Ab(-) group. IFN-gamma, IL-18, MCP-1, MIG, and IP-10 were already elevated at early days post fever onset. Furthermore, levels of IL-18, IP-10, MIG, and MCP-1 were significantly higher in the death group than in the survival group. For the survival group, IFN-gamma and MCP-1 were inversely associated with circulating lymphocytes count and monocytes count, but positively associated with circulating neutrophils count. It is concluded that an interferon-gamma-related cytokine storm was induced post SARS coronavirus infection, and this cytokine storm might be involved in the immunopathological damage in SARS patients.

Epidemiological differences among pneumococcal serotypes

Abstract: The bacterial species Streptococcus pneumoniae consists of 90 immunologically distinct serotypes, of which some possess distinct epidemiological properties. Certain serotypes are much more likely to be associated with nasopharyngeal colonisation than to cause invasive disease. Compared with transient or infrequent colonisers, serotypes carried at high rates by young children may rapidly elicit age-associated natural immunity to invasive disease. Other serotypes seem to be of disproportionate importance as causes of disease in very young infants, in older children, in immunocompromised individuals, or in elderly people. Some serotypes seem to be associated with particular disease syndromes, such as complicated pneumonias in children, or with higher rates of hospitalisation in children or mortality in adults, or are consistently responsible for outbreaks in certain populations. Since pneumococcal conjugate vaccines are directed at specific serotypes, national immunisation advisory committees may wish to consider these serotype-specific properties when considering which vaccine formulation to introduce into a national programme.

Unprecedented genomic diversity of RNA viruses in arthropods reveals the ancestry of negative-sense RNA viruses

Abstract: Many illnesses, including influenza, hemorrhagic fever, and rabies, are caused by a group of viruses called negative-sense RNA viruses. The genetic information—or genome—of these viruses is encoded in strands of RNA that must be copied before they can be translated into the proteins needed to build new viruses. It is currently known that there are at least eight different families of these viruses, which have a wide range of shapes and sizes and arrange their RNA in different ways. Insects, spiders, and other arthropods carry many different RNA viruses. Many of these viruses have not previously been studied, and those that have been studied so far are mainly those that cause diseases in humans and other vertebrates. Researchers therefore only know a limited amount about the diversity of the negative-sense RNA viruses that arthropods harbor and how these viruses evolved. Studying how viruses evolve helps scientists to understand what makes some viruses deadly and others harmless and can also help develop treatments or vaccines for the diseases caused by the viruses. Li, Shi, Tian, Lin, Kang et al. collected 70 species of insects, spiders, centipedes, and other arthropods in China and sequenced all the negative-sense RNA viruses in the creatures. This revealed an enormous number of negative-sense RNA viruses, including 112 new viruses. Many of the newly discovered arthropod viruses appear to be the ancestors of disease-causing viruses, including influenza viruses and the filoviruses—the group that includes the Ebola virus. Indeed, it appears that arthropods host many—if not all—of the negative-sense RNA viruses that cause disease in vertebrates and plants. While documenting the new RNA viruses and how they are related to each other, Li et al. found many different genome structures. Some genomes were segmented, which may play an important role in evolution as segments can be easily swapped to create new genetic combinations. Non-segmented and circular genomes were also found. This genetic diversity suggests that arthropods are likely to have played a key role in the evolution of new viruses by acting as a site where many different viruses can interact and exchange genetic information.

Assessing cost-effectiveness in healthcare: history of the $50,000 per QALY threshold.

Abstract: Cost-effectiveness analyses, particularly in the USA, commonly use a figure of $50,000 per life-year or quality-adjusted life-year gained as a threshold for assessing the cost-effectiveness of an intervention. The history of this practice is ill defined, although it has been linked to the end-stage renal disease kidney dialysis cost-effectiveness literature from the 1980s. The use of $50,000 as a benchmark for assessing the cost-effectiveness of an intervention first emerged in 1992 and became widely used after 1996. The appeal of the $50,000 figure appears to lie in the convenience of a round number rather than in the value of renal dialysis. Rather than arbitrary thresholds, estimates of willingness to pay and the opportunity cost of healthcare resources are needed.

Free‐living, Amphizoic and Opportunistic Amebas

Abstract: Amebas belonging to the genera Naegleria, Acanthamoeba and Balamuthia are free-living, amphizoic and opportunistic protozoa that are ubiquitous in nature. These amebas are found in soil, water and air samples from all over the world. Human infection due to these amebas involving brain, skin, lung and eyes has increased significantly during the last 10 years. The epidemiology, immunology, protozoology, pathology, and clinical features of the infections produced by these protozoa differ strikingly. Infection by the pathogenic Naegleria fowleri is acquired by exposure to polluted water in ponds, swimming pools and man-made lakes. Raised temperatures during the hot summer months or warm water from power plants facilitate the growth of N. fowleri. N. fowleri is a thermophilic ameba that grows well in tropical and subtropical climates. The CNS infection, called Primary Amebic Meningoencephalitis (PAM), produced by N. fowleri is characterized by an acute fulminant meningoencephalitis leading to death 3-7 days after exposure. Victims are healthy, young individuals with a history of recent water-related sport activities. The portal of entry is the olfactory neuroepithelium. The pathologic changes are an acute hemorrhagic necrotizing meningoencephalitis with modest purulent exudate, mainly at the base of the brain, brain-stem and cerebellum. Trophozoites can be seen within the CNS lesions located mainly around blood vessels. Thus far 179 cases have been reported; 81 in the USA alone. Balamuthia mandrillaris and several species of Acanthamoeba are pathogenic "opportunistic" free-living amebas which cause Granulomatous Amebic Encephalitis (GAE) in humans and animals. GAE is an infection, usually seen in debilitated, malnourished individuals, in patients undergoing immunosuppressive therapy for organ transplants and in Acquired Immunodeficiency Syndrome (AIDS). The granulomatous component is negligible, particularly in immunocompromised individuals. Pathologically these amebas produce a patchy, chronic or subacute granulomatous encephalitis with the presence of trophozoites and cysts. The portal of entry is probably through the respiratory tract or an ulceration of the skin reaching the CNS by hematogenous spread. As of October 1, 1996, 166 cases (103 due to Acanthamoeba and 63 due to Balamuthia) of GAE have been reported from around the world. Of these 103 cases due to Acanthamoeba (72 have been reported in the USA alone, > 50 in AIDS). It is well known that several species of Acanthamoeba can also produce, chronic sight threatening ulceration of the cornea called Acanthamoeba keratitis (AK), mostly in contact lens wearers or in individuals with minor corneal abrasions. Hundreds of cases of AK have been documented world wide.