Differing views on the HPV vaccine

In the United States, the rates of vaccination for HPV are currently about 1/3 of females 13 – 17 have completed the vaccination schedule with another 16% have had at least one of the three doses for the vaccination.  With vaccination rates approaching 49%, infection by the strains included in the vaccine have dropped by 56% in girls 14 – 19 in the four years that the vaccine has been available. With such results the CDC is asking healthcare professionals to help them reach rates of 80% or greater as quickly as they can.

CDC Director Tom Frieden described the potential of HPV vaccination in terms of the impact on cancer prevention.

"Our low vaccination rates represent 50,000 preventable tragedies -- 50,000 girls alive today will develop cervical cancer over their lifetime that would have been prevented if we reach 80% vaccination rates,” Frieden said in a statement. “For every year we delay in doing so, another 4,400 girls will develop cervical cancer in their lifetimes."

In contrast to the reports from the US, Japan’s Ministry of Health, Labor and Welfare on June 14 withdrew its recommendation of the vaccine. Japan currently covers the cost of the vaccine for anyone that receives it but the Ministry has concerns of side effects. There are nearly 2000 possible cases of side effects from 3.28 million vaccinations some are severe. Because of this the Ministry is investigating the vaccine and currently allows the vaccination to continue while support is withdrawn but has not made a final decision.

A link between latency and oncogenic viruses

This is a hepatocellular carcinoma in a woodchuck caused by hepadanvirus.

Viral latency is a stage in the lifecycle of some pathogenic viruses that may help a virus hide from the host. In latency viruses become dormant, also called latent, in infected cells. These infections are considered persistent but not chronic because viral replication is not occurring. During this time the viral genome is still present.  The viral genome may be in one of two forms; genetic episomes, distinct objects that may be in the nucleus or cytoplasm in lariat or linear structures, or as a provirus which is the genome of the virus integrated into the host cell’s genome.  Once the virus has entered latency it may need maintenance by the expression of some viral genes. As the cell replicates the daughter cells are already infected and any of the latently infected cells can be stimulated to proceed to lytic infection.

transformation

Though a latent virus may at times be reactivated a more serious complication is the transformation of the cell and forcing it into uncontrolled division.  Many of the known oncogenic viruses including herpesviradae and HPV are shown to have latent periods. The transformation of the infected cell can be from the effects of the maintenance proteins activating growth receptors. When the viral genes insert into the host DNA it may change the expression of host genes and cause transformation of the cell. Either of these effects increases the replication of infected cells and are beneficial for the virus but may increase the harm done to the host.

rapid ID testing

an array of rapid id kits

Much of the testing in the microbiology laboratory uses technology and techniques that haven't

changed much since the 1800’s. Many of the tests used to identify organisms require special reagents or advanced training. Many of the test procedures require extended time from days to weeks depending on what organism is causing one’s disease. Another disadvantage of these testing methods is that many organisms isolated are so similar that it can be difficult to determine what is causing a person to be sick. Because of the limitations of the test available in the microbiology laboratory and advances in our understanding of pathogens rapid testing kits that can identify the causative agent during the course of a doctor’s office visit have been developed and many more will be developed.

prototype of mobile test
LCN

Currently there are rapid identification kits for many common or very serious pathogens such as strep, Malaria, and HIV. Though new tests are being developed at incredible speeds the list of potential pathogens is long and is growing. In class we were shown examples of cassette type rapid tests. With the penetration of the smartphone throughout the world many new types of test are being developed that can take advantage of the always connected nature to not only diagnose but to track the spread in effort to prevent the spread. Because these rapid tests require less specialized training they are beginning to appear on store shelves so that you can know the results of the test and inform the doctor so that he can start the treatment much quicker.

Better protection by saliva as we age

Better protection by saliva as we age

from UCLA 

Recently studies discovered that important changes in saliva happen as we age. But first what is saliva. Saliva is a secretion found in the oral cavity. It is required for many things. It initiates digestion, helps maintain teeth, is necessary for oral homeostasis, and has antimicrobial properties. Saliva is approximately 94% water the rest is an interesting mix of molecules. Many of the minor constituents have biologic activity required for the roles that saliva plays.

One of the major changes recently discovered is that as we age the glycoproteins that are expressed change. One change is that older people express glycoproteins with more terminal alpha 2-3/6-linked sialic acid residues¹. These sialic acid residues bind the hemagglutinin(HA) on the surface of viral particles. This provides protection against influenza. Qin et. al.¹ showed that the binding of the virus particles to the glycoprotein increases  and that the composition of glycoproteins changes to a mixture that has more binding sites as we age. This shows that even though as we age our immune system declines in effectiveness we have other protective mechanisms that continue to protect and even improve in their effectiveness as we age. 

1. Yannan Qin, Yaogang Zhong, Minzhi Zhu, Liuyi Dang, Hanjie Yu, Zhuo Chen, Wentian Chen, Xiurong Wang, Hua Zhang, and Zheng Li Age- and Sex-Associated Differences in the Glycopatterns of Human Salivary Glycoproteins and Their Roles against Influenza A Virus
   Journal of Proteome Research 2013 12 (6), 2742-2754

MERS- CoV an emerging virus

from presstv

Coronaviruses are of emerging concern. From the SARS outbreak to the current threat of MERS coronaviruses are definitely pathogens of concern.  What are coronaviruses and specifically MERS-CoV?  Coronaviruses are positive sense RNA viruses that have bulbous projections that appear like the solar corona. Coronaviruses have the largest genome of the RNA viruses. Upper respiratory and gastrointestinal tracts can be infected by coronaviruses. MERS-CoV was identified in 2012 as the cause of a respiratory illness in people. Discovery of this virus makes it the sixth coronavirus known to infect humans.  MERS-CoV is like the SARS-CoV in that it also involves the lower respiratory tract and is a cause of severe acute respiratory disease.

from abc news

Current reports are that the MERS-CoV has out of 55 cases 31 patients died. Whether this is from underreporting of mild cases or increased virulence is unknown. Symptoms start with cold or flu like respiratory symptoms. Like SARS-CoV, the MERS-CoV progresses to severe acute respiratory disease. Currently all cases are like to four Middle East countries: Saudi Arabia, Jordan, Qatar, and UAE. Travelers to these countries have also shown MERS-CoV. Close contacts have also presented with MERS-CoV indicating that it is transferable from person to person. Ease of transmission is currently unknown. In France, at least one case of nosocomial infection was reported. It is important to remember that though this is a rare it has the potential to become an important pathogen with high mortality rates and unknown transmission rates.

Blood volume effects recovery in bacteremia in automated blood culture systems

Automated blood culture systems have made bacteremia much easier to detect. The current systems use a prepared bottle that has responds to the growth of bacteria to induce an observable change. These systems use color, pressure change, or chemical change to detect the growth of bacteria in the inoculated bottle. These automated systems require a ratio of blood to medium between 1:10 and 1:5. If the volume of blood is too low there may not be enough colony forming units for detection. And if the ratio goes below 1:5 blood components may not be diluted enough and may inhibit bacterial growth. A study performed at China Medical University Hospital in Taichung, Taiwan1 showed the effects that blood volume can have on detection of bacteremia. Hsiu-Hsien et. al. performed this study were they retrained the ER department where 97% of blood cultures were done with less than 5mL of blood  and after training greater than 70% of blood cultures were done with at least 5mL of blood. In this study, it is evident that the amount of blood used has great impact on the recovery of organisms. They showed that with blood volumes of 5-10 ml that recovery increased by 17% over low volumes. Volumes greater than 10mL showed lower recovery rates than smaller volumes.

blood culture bottles

http://www.medicalobserver.com.au/assets/images/07-09-12-germgems.jpg

1 Hsiu-Hsien Lin et.al.  Evaluation of the blood volume effect on the diagnosis of bacteremia in automated blood culture systems  Journal of Microbiology, Immunology and Infection (2013) 46, 48-52 Http://www.sciencedirect.com/science/article/pii/S1684118212000503

post for the week of June 2

Welcome to my first blog post.

This is my blog for the infectious disease course, CLS538 at UAB. The purpose of this is to discuss the class and current developments in clinical microbiology.

I am a student in the Clinical Laboratory Science masters program at the University of Alabama at Birmingham. After all the other experiences I have had in school I am really enjoying the experiences and course work in this masters program. One thing that I think drew me to this program is the fact that as a medical technologist what I do in the laboratory has a direct effect on the health of a patient. What I do is helping others.

hCMV infected cells

http://www.meddean.luc.edu/lumen/MedEd/orfpath/images/fig131x.jpg