Infectious Disease

structure:

Bacterium E-Coli consists of these characteristics, they are in the family of enterobacteria caleae. gram negative bacteria, Ros shaped, Non spore forming bacteria. They can grow under aerobic and anaerobic conditions. They do not produce enterotoxins. (PublicHealth,2012.)

Size:

Bacteria are the prokaryotic and unicellular organism. Due to presence pf the rigid cells into bacteria, it always maintains the proper shape (Tibayrenc and Ayala, 2017). However, bacteria vary in size and shape. When viewed under the microscope, bacteria can be seen in different shapes shape such as rod like structure (Bacillus), spiral type (Vibrio) and sphere shaped (Coccus) (Kriventseva et al. 2018).

Reproduction:

Bacterial reproduction occurs in different process, such as Binary Fission, conidia and budding. In binary fission, the single bacterial cells divide and firm two equal sized cells (Ma et al. 2016). On the other hand, ibn case of budding, bacterial cells leads to production of small swellings at one side of their body.. This outgrowth is referred as bud which is then separated from mother body and grow as the new organism (Kriventseva et al. 2018).

Structure:

Viruses are the smallest agents that can direct their own replication (Tibayrenc and Ayala, 2017). They are also ultramicroscopic, too small to be seen with the light microscope, as they can be visualized using the electron microscope. They require living cells for there own growth and reproduce within there host cells by mechanisms different from bacterial binary fission.

Size:

Viruses can vary in size, (e.g.) small pox viruses, bellow the limit of being seen under the light. As they were often referred to as filterable viruses or filterable agents as they pass through the filters which retain bacteria (Tibayrenc and Ayala, 2017). This is done through the direct observation with the electron microscope. Viruses are surrounded by a protein coat called capsid (Kriventseva et al. 2018).

Reproduction:

Virus attaches to protein coat of host cells, penetrates into the cell membrane and then insert the genetic material of virus into the host cell (Kriventseva et al. 2018). Then the genetic material of virus start replication by using genetic particles of the host cells. Then new protein coat is made which is then attached to the new genetic codes for forming new viruses. After formation of new virus, the host cell burst in terms of realising the new viruses.

Structure and size:

Fungi consist of organisms such as yeast and molds. Growth depends on each of these, to be either single celled yeasts, or multicellular molds, some fungi may produce human diseases, this depends on the conditions of growth (Tibayrenc and Ayala, 2017). Classification of fungi is based on their appearance and method of formation of sexual spores, or asexual spores. Yeasts are microscopic one celled fungus which reproduce by forming buds on the mother cell, they produce sexual spores followed by the connection of two separate cells fusing together.

As compered to reproduction of virus, in case of fungi, reproduction can be occurred in both sexual and asexual form (Kriventseva et al. 2018). In case of sexual reproduction, two sex cells united with assembly of their nucleus. Through this assemble of nucleus of two sex cell, new spores are developed which then grow into new organism (Ma et al. 2016).

The asexual reproduction in fungi is occurred by fragmentation and breaking up of the fungi body or thallus. If the environment is favourable for the asexual reproduction then each fragment that is develop from fungi body grows into new organism.

Protoctista:

Structure:

The Protoctista (Protista.) are eukaryotic organisms, usually composed of a single cell or a colony of the same cells (Kriventseva et al. 2018). They live in water, moist conditions. As parasites and other symbionts in the components of multicellular eukaryotes. They do not share characteristics like fungi, the two protozoan groups called trypanosomes and dinoflagellates.

Size:

Recent biological studies show that average size of the Protoctista is between 10 micro meter to 100 micrometres (Tibayrenc and Ayala, 2017). From the recent evidence it has been n that seen that largest protist is Xenophyophore, which is seen ion the 800 to 6000-meter depth under the ocean.

Reproduction:

Protists are the diverse group of organisms that reproduce both in sexual and asexual process. in case of sexual reproduction, parent nucleus undergoes the meiosis process in order to produce two gametes (Ma et al. 2016). After the formation of gametes, two gametes are united in order to produce the new cell. During the sexual process of reproduction, genetic mixing takes place which leads to form genetic diversity.

Infectious disease:

According to World Health Organisation (WHO), infectious disease can be referred as health disorders that are caused by pathogens such as viruses, bacteria, parasites, and fungi [WHO, 2019] . These are contagious, which can be spread both indirectly and directly from one person to the other.

For example, zoonotic disease is infectious disease in animals that is caused by virus, which then transmitted to human body due to contact with animals suffering from this disease (Weiner et al. 2016).

Pathogens:

Pathogen can be refereed as the anything that has ability to cause disease (Semenza et al. 2016). According to WHO pathogen are the infections agents or germs such as virus, fungi and bacteria, that have been associated with spreading different disease.

Different types of pathogens:

There are different types of pathogens in the environment such as bacteria, fungi (plasmodium and amoeba), parasitic worms (roundworm and flatworm) and protists (Marder et al. 2017). In this context, the Asian Avian Influenza A(H5N1) virus is associated with highly life-threatening infections in human body [WHO, 2019].

3a.) Antibiotics are powerful medicines which fight bacterial infections in the body, they will either kill the bacteria or stop it from reproducing, this happens due to the inhibition of protein synthesis, damage to the DNA and cell wall known as biosynthesis. (Walsh,2000.) C.difficile bacterium, is a gram positive, spore forming, anaerobic bacilli. It is a dangerous infection (HAIs.) affecting immunocompromised individuals, (e.g.) elderly, children, patients undergoing antibiotic use. Its resistance to dehydration makes it dangerous as it has a gram-positive cell wall and its ability to form spores (Marder et al. 2017). The spores are its mechanisms to survive the harsh conditions.

3b.) C. difficile mechanisms of antibiotic resistance, by altering its shape and structure, proteins. It will alter the strength of antibiotics used to target the specific cellular features. E.g. metronidazole resistance, nitrogen leads to nitrogen reduction, iron uptake, DNA repair. Vancomycin resistance, AA changes in the proteins (MurG) This is important as it is responsible for peptidoglycan synthesis, vancomycin will no longer be able to bind to the specific protein to inactivate it and therefore kill the bacterium causing the infection (Weiner et al. 2016).

4.) Global efforts are being Made to vaccinate the population against polio so the disease is no longer going to spread person to person, the population will not be coming into the contact with the disease known as herd immunity (Sands et al. 2016). As nobody will be susceptible to the disease, the disease can be avoided, and people will not be able to contract the disease via personal contact. As polio is a serious viral infection which is common in Pakistan and Afghanistan, ‘figures have shown in 1988, there were 350,0000 annual cases of wild polio virus from 125 countries’, ‘2017, there were 22 polio virus cases reported in only two countries (WHO, 2019).

Reference list:

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