RATTANALAK JITTUNGDEE

[RATTANALAK JITTUNGDEE]

Rattanalak Jittungdee
6438165

Epidemiology is the study of how often diseases occur in different groups of people and why. Epidemiological information is used to plan and evaluate strategies to prevent illness and as a guide to the management of patients in whom the disease has already developed. The study of the outbreak can also help in planning, controlling, and monitoring the spread of the disease.

For example, a study by Leandro, André S et al. (2022) study about Citywide Integrated Aedes aegypti Mosquito Surveillance as Early Warning System for Arbovirus Transmission, Brazil. In this study, The Aedes aegypti mosquito is the primary vector of arboviruses. This mosquito species is common in urbanized areas in the tropics because it is highly adapted to live in close association with humans, preferentially feeding on the blood of human hosts and laying eggs in containers located around human dwellings.

They report on a 4-year integrated citywide vector surveillance approach that involved extensive use of adult mosquito traps, molecular diagnostic testing for natural arbovirus infection in live collected mosquito specimens, construction of transmission risk maps, and performance of timely vector control intervention <48 h after mosquito collection. In this scheme, vector control was intensified in areas with a higher risk for transmission instead of maintaining homogeneous vector control efforts over the landscape. In addition, they evaluated the correspondence of larval- and adult-based indices with the epidemiologic trend in the city of Foz do Iguaçu, Brazil, during 2017–2020.

The results show, that comparing the predictive ability of traditional versus adult indices revealed that indices based on adult trapping consistently performed much better than indices based on larval surveys. and one criterion that could be used to prioritize areas is the occurrence of Ae. aegypti female mosquitoes are naturally infected with DENV, ZIKV, or CHIKV. In Foz do Iguaçu, an inspection of the 3,476 Adultraps took 4 days, and real-time qPCR results were available, on average, 36 h after all Adultraps were inspected and live mosquitoes collected.

In conclusion, They conducted a 4-year citywide study to deepen the entomologic and epidemiologic features of dengue transmission in Foz do Iguaçu by focusing on developing indicators based on adult mosquito trapping. They proposed a surveillance system that can predict a dengue outbreak with high accuracy, and indices based on adult trapping are able to predict a dengue outbreak 4 weeks after DENV detection in adult mosquitoes. In addition, the adoption of easily accessible technological resources makes it possible for the model to be replicated in other localities.

Ref: Leandro, A. S., de Castro, W., Lopes, R. D., Delai, R. M., Villela, D., & de-Freitas, R. M. (2022). Citywide Integrated Aedes aegypti Mosquito Surveillance as Early Warning System for Arbovirus Transmission, Brazil. Emerging infectious diseases, 28(4), 701–706. https://doi.org/10.3201/eid2804.211547

[RATTANALAK JITTUNGDEE]

Rattanalak Jittungdee
student ID : 6438165

1. Describe in the group discussion; character, shape, how to collect.
1.1 Character of ovary dissection from the mosquitoes
– Parous ovary: the tracheoles are released because the mosquitoes that have been taking a blood meal and oviposited before.
– Nulliparous ovary: can see the many coiled tracheoles inside the ovary
1.2 Shape of the ovary
– can see the two oval lobes of the ovary when you pull the segments 7th and 8th out.
1.3 How to collect?
– Anesthetize mosquitoes with ether.
– Pull out the legs and wings of the mosquito.
– Use a needle to hold the mosquito with one hand.
– Use another needle to gently pull out the 7th and 8th segments of the mosquito together.
– You will see 2 bunches of ovaries attached to it.
– Then cut the ovaries out and place them on the prepared slides.
– Wait for it to dry and then observe it with a microscope.

2. How important of blood determination and mosquito parity rate?
: if we know the source of blood in the vector we can determine the relation between host and mosquitoes, host preference, host-feeding pattern, and proportion in mosquitoes. and parity rate causes us to know that areas have more or less breeding places that are connected with the transmission rate. also counting the number of ovarioles from captured mosquitoes can determine the age structure of the population.
– Methods of determination
: – The methods to determine the blood source in the mosquito can use in many ways including
• the precipitin test
• enzyme-linked immunosorbent assay (ELISA)
• multiplex PCR/DNA barcode
• Microsatellites
• Mass spectrometry
– The method of age determination including
• Parity rate in ovary dissection that each dilatation represents one gonotrophic cycle.
• Molecular markers: detect some proteins that increase or decrease after being oviposited of mosquitoes.
– Application of these 2 parameters
: can apply to surveillance and monitoring to determine vector capacity in those areas. cause to know that transmission of disease is more or less and to control the vector as soon as possible. For example, the age of female mosquitoes is determined by multiplying the number of dilatation of tracheoles in the ovary and the number of days of the gonotrophic cycle. also, the blood determination can find a host-feeding pattern and host preference in the vector.

[RATTANALAK JITTUNGDEE]

Dear Ajan Patchara,

These are conclusions regarding the plan and actions to support and react to the case scenario from five of us (Vanheuang, Rattanalak, Tipawan, Oranit, and Panachaya).

1. For routine work in vector surveillance of malaria, the objective is for planning the surveillance of vectors, monitoring, and planning control programs for early warning of disease outbreaks in a specific area, and for evaluating the effect of vector control.
The plan for routine work in vector surveillance includes objective, planning, method, analysis, conclusion, and interpretation of the result.
• Objective setting: Set the objectives of the vector surveillance based on the study such as identifying the transmission pattern, investigating the habits and habitats of the local vector species, to monitor the seasonality and abundance of the vector population in terms of early warning of malaria outbreak and also to plan for a vector control program (select the appropriate method with appropriate time and place).
• Planning: After we understand the objectives, we should consider the study design. Such as type of study, design method, and techniques that will use for collecting the samples and laboratory investigation.
• Method:
– Data collecting: preparing for data collecting and data recording such as the form that will use to record and preserve the sample inappropriate way for further investigation based on the purpose of the study
– Analysis: analysis of the data from lab results using Microsoft Excel and analyze in terms of graphs and tables. Then, conclude the result and report the result of the surveillance by using the description of the study, worksheet report, discussion, comment, interpretation, and conclusion.

2. For the scenario of Malaria outbreak on the Thai-Myanmar border in Tak province,
• Objectives:
– To identify the causes of malaria infection on the Thai-Myanmar border in Tak province
– To identify the species of mosquito vector responsible for malaria transmission in this area
– To eliminate or control malarial vectors on the Thai-Myanmar border in Tak province
– To evaluate the efficacy of the vector control program
• Planning:
– Select the appropriate study design: A cross-sectional study identifying the prevalence of malaria in vectors and patients in this area.
– Select the appropriate sampling techniques: systematic sampling method to collect the sample to get representative of sample in that area and we need to know the sample size and sampling interval.
– Select the appropriate technique for laboratory investigation
– Planning for the timeline of the project to set a schedule for sample collecting, laboratory investigation, and data analysis
• Program activities: In Determining what to do each day, we should know the timing and the manpower beforehand to separate the tasks responsibilities.
• Methods: Methods used to collect data or collect samples. which should have a form to record information The equipment used to collect samples corresponds to the survey area including methods for preserving samples for experimentation or inspection and technique that will use in laboratory investigation.
In this case, for the adult stage of Anopheles mosquito collection, the trapping method should be used such as the BG trapping or light trapping. After mosquito collection, we preserve the sample inappropriate ways such as preserving it in silica bead, putting it in the primary and secondary containers with ice-pack, and labeling. Then transport to the laboratory for study purposes. After that, the identification of mosquito species will be performed in the next step using morphology identification and molecular techniques.
• Analysis: Gathering the collected data and generating the data in terms of graphs with the programs such as Microsoft Excel. Some data should be calculated according to the formula before concluding. After analyzing concluding should be done.
• Reports: Reports the investigation result which includes the methods and techniques used, and states the conclusion and results of this program. Discuss the results whether meet the objectives or not. Then, discuss the success and failure or advantages and limitations of this program. The methods to deal with those mistakes. As well as, how to bring this information to apply in the new vector control program. Finally, show the trend of further developing research.
So, we can see the problem and suggest to villagers to know and waring about the disease outbreak in this area and suggest how to prevent and control the malaria outbreak in the Thai-Myanmar border of Tak province.

Thank you very much.

Yours sincerely,
Vanheuang, Rattanalak, Tipawan, Oranit and Panachaya

[RATTANALAK JITTUNGDEE]

Rattanalak Jittungdee 6438165

1.Routine work of vector surveillance for malaria
I agree with Mr.Vanheuang’s opinion in Item 1 that surveys should be designed to collect data, for example, if we want to collect data on adult mosquitoes or larvae. We should choose that Anopheles spp. that are the main vectors for malaria. The life period and habitat of this species should be studied. To store information according to the data recording plan that has been set up. Based on the objective of the survey is to monitor malaria vectors.
– Long-term sampling is a survey that is often done to look at the increase or decrease of vectors in that area. Although it is a longer method to draw conclusions about how the disease fluctuates.
– Short-term sampling is a survey that often goes into areas where the infection has been reported. This may be surveyed to confirm the prevalence of vector vectors in that area and the rate of vector transmission. The results will lead to an assessment to control the situation in that area.

2. There is the outbreak of malaria in Thai-Myanmar border in Tak province. (2.5 scores) Please explain the detail in term of
– Objective: This part depends on what we want to do for what purpose.
 To identify the source of malaria outbreaks in reported areas
 To control the spread of disease
 To study the spread of disease and its vectors
– Planning: The planning will be adjusted according to the objectives of the work. which we must have knowledge of the habitat and behavior of mosquitoes and choose a study method to suit the results we want
 Identify the carrier mosquito species: We need to know the terrain of the outbreak area. Corresponding to the habitat of what types of mosquitoes we may encounter in the area. When is the time during which mosquito species are active? A cross-sectional study may be used to collect data.
 Outbreak Control: We need to know what the outbreak area looks like. life of villagers How is the habitat How many outbreaks How are the number of vectors and the rate of the outbreak? If the infection is more children or adults, a retrospective study or cross-sectional study may be used.
 Disease transmission rates and vectors: Know how many mosquito breeding areas the area has. What is the number of infected people? The number of mosquitoes that can be found in the survey such as using methods capture-recapture method to measure mosquito population prevalence will affect the spread of the disease as well. A retrospective study or a cross-sectional study may be used.
– Program activities: Determining what to do each day, for example, in the morning to collect samples or data in Area A, and in the afternoon to collect samples or data in Area B, etc.
– Methods: Methods used to collect data or collect samples. which should have a form to record information The equipment used to collect samples corresponds to the survey area. including methods for preserving samples for experimentation or inspection
 The use of BG trapping to trap adult mosquitoes or the use of devices used to catch larvae in water sources that may have Anopheles mosquitoes. Follow different areas of the survey area and map where traps are placed. and save the data
 Preservation of collected samples which we want the example to be complete. for effective monitoring such as Collection in tubes containing silica beads, for example, and labeled with type of sample, date of collection, area of collection. including sample collectors
 Transport of samples that can be stored in a sealed and strong container to prevent damage or loss of samples
 Laboratory Examination: Morphological Classification, Molecular species identification including the detection of malaria in mosquito samples obtained
– Analysis: Bringing the data obtained from local surveys and laboratory results to be recorded in a digital system such as Excel, then analyzed and summarized.
– Reports: describe the results of the survey. Discuss how well the results meet the objectives. result meet the purpose or not What needs to be improved in the next study?

[RATTANALAK JITTUNGDEE]

TMEN513 Lab exam: Cockroaches and bugs
Name: Rattanalak Jittungdee ID:6438165

Question1: Please describe how you identify the cockroaches (selecting at least two species)
Answers:
1.Periplaneta americana (American cockroaches): is the largest of the house-infesting roaches and a major pest in the United States. we can identify by;
– Color: typically reddish-brown with a yellowish band on the back of the pronotal shield.
– Legs: They have 6 legs
– Shape: Oval
– Size: Adults may range between 1 1/4” to 2 1/8” (32-54 mm) in length
– Antennae: Filiform antennae
– Region: American cockroaches are found worldwide
2.Neostylopyga rhombifolia (Harlequin cockroaches): originated in Indo-Malaysia, found in the northern part of Australia, Mexico, and also found in South California. we can identify by;
– The length varies from 20 to 27 mm.
– The tegmina (forewings) of both sexes are small lobes, only about 4 mm long, and hind wings are entirely lacking.
– Its distinctive colors and patterns make this roach one of the most beautiful species kept as a pet by many enthusiasts around the world.
– Very fast in its movements this species is an egg layer and can climb smooth surfaces.
– In optimal conditions females can lay a large quantity of ootheca (egg case) containing about 15-30 eggs each.
– Juveniles have a tan uniform color, molt after molt they acquire the characteristic design that distinguishes adults.
– The Harlequin Cockroach has the ability to produce a chemical (amyl acetate) that smells like pear drops which it uses to defend itself against predators, therefore it would not be a good choice to use it as feeders for reptiles and amphibians.

Question2: What is the difference between genus Triatoma and Rhodnius?
Answers: The difference between genus Triatoma and Rhodnius are;
Triatoma spp.:
– antennae arise from the sides of the head at the middle, between eyes and the tip.
Rhodnius spp.:
– antennae arise from the sides of the head at the anterior end.

[RATTANALAK JITTUNGDEE]

TMEN513 lab exam Tick and mites
Student name: Rattanalak Jittungdee ID: 6438165

Question 1: What is the respiratory organ of the suborder Astigmata? How do they breathe?
Answers: The suborder Astigmata are non-existent in the external openings; in the Astigmata gas exchange is through the integument.

Question 2: What is the difference between hard ticks and soft ticks? How do you differentiate between male and female hard ticks?
Answer:
The difference between hard ticks and soft ticks:
– Hard ticks have a “plate” on their back that is called a scutum. Also, hard ticks have mouthparts that are visible when the tick is viewed from above.
– Soft ticks appear to have a wrinkled body; lack a scutum, mouthparts are located on the underside of the body so that the front portion of the tick’s body hides the mouthparts.

The differentiate between male and female hard ticks: Hard tick adult males and females have different coloration and females are somewhat larger than males.
Male hard ticks have an inflexible scutum that spans the entire top side or dorsal surface; among females, the scutum or dorsal shield is less than half the size of males and is limited to a small region directly behind the head (capitulum).

Question 3: Please describe how you characterize the mites (at least two groups).
Answer: Mite, any of numerous species of tiny arthropods, members of the mite and tick subclass Acari (class Arachnida), that live in a wide range of habitats, including brackish water, fresh water, hot springs, soil, plants, and (as parasites) animals, including humans.
– House dust mites (Dermatophagoides sp.) are globular in shape, clear to creamy white in color, with hairs on their legs and body. They are a small mite, cuticle finely or coarsely wrinkled, and has anus sucker ventral; in males, the genital organ located between last 2 pairs of legs; in the female has reverse Y or V-shape vulva.
– Follicle mites (Demodex folliculorum) are very small mites, have elongated, semi-transparent bodies made up of two fused segments, with the first segment having 8 stumpy legs attached; legs are located together on the anterior part of the body. The body is covered in scales that help them attach to your hair follicles. Demodex mites have mouthparts designed to consume skin cells, oil, and hormones found in your hair follicles.

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