I was given the opportunity to collect ticks at a few different sites through-out the trip. The staff that are involved in this activity really enjoy getting outside and you can only drag on nice days! So you get out of the office. Maine is a huge area so there are lots of sites.
On Friday I went to Crescent Beach State Park, a park that is full during the summer months and again no warning signs visible.
As well as collecting ticks the lab has also been involved in analysis of the type of vegetation that tick abundance is noted in, recognising the different types of vegetation that can be found in the same areas.
While at Crescent Beach the vegetation was different on either side of the path in some areas:
The path through the park
On the left side- lots of tall trees more tightly packed together with minimal amounts of ground shrubs – this area is less friendly to ticks.
Right side of the path- much more ground shrubs and the trees appear more spaced with more sunlight getting in- this type of vegetation is very tick friendly.
During the drags ticks are collecting into little vials and taken back to the lab.
Once back in the lab all the ticks have to be identified and a data sheet is completed.
The sex is identified and data on how/where and when they were collected.
The ticks are used in a range of different projects, over the years the lab has been involved in many projects looking at sites of tick abundance and the infections they carry. Most of the ticks collected at the moment are analysed for co-infections and the presence of powasson virus, also the changes in focality at different sites i.e. some sites can have a large number of infected ticks in one area of a park and the rest of the park has no infected ticks.
Rebecca Robich is an Entomologist with the Maine Medical Research Lab and she oversees all the lab work that is undertaken. I asked Rebecca to explain the process used with Polymerase chain reaction (PCR). PCR is used when detecting bacteria or viruses. It is a method widely used in molecular biology to make multiple copies of a specific DNA segment. Using PCR, a single copy of a DNA sequence is exponentially amplified to generate thousands to millions of more copies of the particular DNA segment .
The lab are looking at Powasson virus (Tick borne encephalitis in Europe)at Wells reserve, some of the ticks collected within the reserve have tested positive.
Powasson is a virus and is a + ve sense RNA virus. In humans we make RNA which is single stranded and made in the nucleus, it can be turned into proteins within the body and fulfils its use within the body. Viruses or pathogens can be DNA or RNA , most vector borne viruses are RNA. DNA virus integrate into DNA and can only be located in one host, RNA viruses do not enter the nuclei and can go from host to host which is true of tick borne diseases. To start the PCR process the powasson RNA has to be converted to double stranded c DNA, using reverse transcriptase and then the second step is to replicate it over and over again. Once replicated the c DNA is looked at alongside a control to identify the individual coding of each virus.
Two of the areas within the reserve have had ticks positive for powasson virus and the use of PCR allows for identification of the strains. This will demonstrate if it is the same strain at both sites or are they completely different strains.
Once the PCR has identified the DNA code for the virus is matched onto a database where all codes are stored, this will allow for matching to any previously identified viruses.
Once the PCR can identify whether the two groups of ticks carry the same DNA/RNA lead the research to look at other aspects such as the differences in vegetation/small mammals etc at the sites.