Seroepidemiologic Studies - Science topic

Transfusion-transmitted infections are a threat to people's lives, and this is due to unsafe blood donation and improper pre-transfusion testing procedures. In line with this, what are some of the protocols in place to prevent these infections? What are some of the diseases prevented by these protocols?

My study is focused on estimating the seroprevalence of certain bacteria using ELISA. The seropositivity varies with age with high prevalence among 10-15 yrs and low for <5 yrs. I do have five bands of age strata and the survey is a population-based survey. My sample size is about 1000. My question is how can I distribute the sample size among 5 bands of age based on their prevalence (already reported in another research report) using the RULE of THUMB?

Hello,

I need your help. I am working on a SARS-Cov2 seroprevalence study. I will isolate the plasmas using a ficoll gradient; I would also like to keep the PBMCs for future studies. I want to store them at -80°C as I do not have a liquid nitrogen tank. According to your experiments, how long could I keep the cells at -80°C and especially what medium should I use for freezing.

Thank you.

Dear Researchers,

In this corona pandemic, we are looking into mainly three possible options of combat i) drugs to treat after infection, ii) vaccine and iii) herd immunity. No the first two options seems to be just a inch of distance as some labs, groups of researchers demands its success and availability in near future and simultaneously some groups raises questions about these like success rate and side effects. Finally the third option comes in front and shows some hope in near future as it was early estimated that about 60% of a community needs to get infected but the recent calculations by the mathematicians from the University of Nottingham and University of Stockholm pointed out that it is enough if 43% of a community gets infected¹. Again a seroprevalence survey by Indian Council of Medical Research showed that in Kolkata and surrounding area of West Bengal, India showed that over 14% people have developed COVID-19 antibodies². So are we approaching towards herd immunity?

Hope you will input you view regarding herd immunity.

Thank you.

1.

2. https://www.firstpost.com/health/over-14-kolkata-residents-have-covid-19-antibodies-finds-icmr-survey-city-far-from-developing-herd-immunity-say-doctors-8535621.html

In Spain, the Goverment give public preeliminary results about the seroprevalence study of Covid-19:

https://www.newtral.es/wp-content/uploads/2020/05/ENE-COVID_Informe-preliminar-cierre-de-la-primera-ronda_13Mayo2020-1.pdf

5% of seropravelence in Spain... this is aproxm. five more times that you can modeled with Corean and German information about Covid, and about the double that another study of seroprevalence with a major "n" in Galicia (Spain) using the same IC (inmunocromatography).

Do you see any wrong in the experiment desing??

Dear researchers,

I come across some papers in Epidemiology field where they use geometric mean concentration for antibody titer. I wonder why do we want to use geometric mean concentration, what is the advantage(s) and disadvantage(s) of using this calculation for antibody titer.

Also if any one can suggest a good reference to read about it, I would really appreciate.

Thank you.

I've been running indirect ELISAs using Apical Membrane Antigen-1 and Merozoite Surface Protein-1 to test serum samples from a low transmission region for previous exposure to malaria. A majority of our sample are under the age of 18, however the literature is unclear as to what the window for detecting malaria antibodies are using these antigens. Does concordance between antigens suggest a more recent exposure? If someone could elaborate or recommend literature explaining detection thresholds and windows for these two antigens I would greatly appreciate it.