Monday 28 November 2022

Top Antibiotics That Treat Infection

 Image: L.Weakley

Imagine how difficult life would be without antibiotics. Since the early years of the 20th century, highly effective pharmaceutical antibiotics have saved millions of lives, but archeological evidence indicates that physicians in the ancient civilizations of Egypt and China treated microbial infections with mold. Ever since Alexander Fleming pioneered the use of therapeutic penicillin in the late 1920s, the development of antibiotics has advanced very significantly, but this is a changing field because many bacterial pathogens evolve and mutate in order to survive antibiotic treatments. With all this in mind, let's take a look at the main antibiotic classes and how they treat infections.

By Lizzie Weakley


These antibiotics were prominently used during the worst months of the COVID-19 pandemic to treat patients whose weakened immune systems allowed bacterial pulmonary infections to develop. Unfortunately, it appears that certain bacterial families linked to respiratory disease are becoming resistant to macrolides.




Since the release of tetracycline in the 1950s, this antibiotic class has become known as the "Swiss Army knife of antibiotics." Tetracycline can be used to treat a wide range of microbe species, and it can alleviate many conditions that include urinary tract infections and even some types of dermatitis. In recent decades, this antibiotic has been reformulated to treat sexually transmitted infections that have evolved through various mutations.



This is the grandfather of modern antibiotics, and one of most significant medical advances of the previous century. The numerous derivatives of penicillin include ampicillin trihydrate, a suspension formula that is commonly used by veterinarians to treat severe staphylococcal infections. Penicillin is still used as part of oral surgery procedures that have a greater risk of infection.



This is an advanced class of antibiotics that has come a long way since the days of penicillin. The advantage of cephalosporin medications is that they rarely provide provoke allergic reactions or strong side effects. Quite a few infections can be controlled with this antibiotic class, which can also be formulated at hospitals for specific conditions.



This type of antibiotic medication is only administered under close medical supervision, and it is mostly used to treat patients whose options are diminished because of underlying chronic conditions. When cancer patients go through chemotherapy, fluoroquinolone is sometimes prescribed when there is a strong risk of bacterial infection.


It should be noted that the antibiotic classes listed above share an important common denominator: They inhibit the spread of bacteria within patients, thus allowing the immune system to handle a lower pathogen load.


Pharmaceutical Microbiology Resources (

Small Study Makes Big Steps toward Finding a Vaccine for Malaria


Malaria is carried by mosquitoes and is one of the most well-known and most dreaded diseases in the world. Each year, the disease affects hundreds of millions of people and kills over half a million.

While strides have been made toward creating a vaccine, no one has been able to prevent malaria infection at a high enough percentage for it to be considered successful. That may be changing soon, however, thanks to the diligent work of some persistent scientists.

Current Malaria Treatments

Malaria treatments are currently based on a regimen of early detection and then treatment with various anti-malaria drugs. In order to successfully treat a malaria infection, the physician must complete what is known as a parasitological diagnosis — a blood sample is taken from an infected patient and treated with acridine orange, which is a fluorescent dye that reacts with the malaria parasites in the blood. The dye causes the parasites to change color and appear brightly when seen under a specific type of microscope.

This is necessary because there are actually two forms of malaria, categorized by the type of parasite that is infecting the blood.

Plasmodium falciparum is the most common type of malaria. Unfortunately it is also the most deadly form of the virus. Its companion, plasmodium vivax (P.vivax), is far less common. There are also a couple of very rare forms of the virus, designated as plasmodium ovule and plasmodium malariae, which look very similar to P.vivax and may be more difficult to diagnose.

Once the specific strain of malaria has been determined, a treatment plan can be set up to best defeat the virus.

Vaccine Progress

Right now, in spite of the enormous number of cases each year, scientists have not been able to create a vaccine that protects against malaria. A new, albeit small, study has found a vaccine that may protect adults from the most common form of malaria, P. Falciparum, for up to a full year.

By injecting a weakened version of the live virus into 59 of the 101 study volunteers and then exposing them to the virus, scientists were surprised to see that it protected those injected with the vaccine up to 50% of the time.

Additionally, those who are protected by the vaccine seem to be unable to spread the virus to others, so even if they are bitten by an infected mosquito, the insect will not be able to transmit the virus. 

Moving Forward

Though it doesn’t offer 100% protection, this vaccine is a great step forward in getting rid of the mosquito-borne virus that affects so many people every year. In 2015 alone, there were an estimated 214 million cases of Malaria worldwide, according to the World Health Organization. Imagine the impact this vaccine could make, even with the 50% protection the vaccine currently offers — how many of those 214 million cases wouldn’t have to happen at all?

The vaccine in its current form is already making an impact, both in areas affected by the virus and in the scientific communities. The eventual goal is to use this vaccine to help prevent malaria infections in African children, who are often the hardest hit by the disease.

While we’re not there yet, this progress toward finding a fully functional vaccine is incredibly inspiring, and it will be amazing to see what these scientists come up with next.

Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

Monday 21 November 2022

Tracking and tracing to the root cause: case studies in microbial contamination


In this article, pharmaceutical microbiologist and contamination control expert Tim Sandle presents three microbial contamination investigation case studies, highlighting the key lessons for pharmaceutical microbiologists to take away and the underlying importance of identifying the root cause of microbial data deviations.


One of the main activities of the pharmaceutical microbiologist is with determining the contamination control strategy and proactively identifying measures to lower identified risks and, where risks remain of concern, to introduce monitoring. However, there will invariably be microbial recovery, from product (intermediate and finished), from water, cleanrooms and other utilities. 



A common term of these events is ‘microbial data deviations’, although other terminology can apply. These microbial events require investigation and the importance of such an investigation is elevated where there is recurrence. While investigations are referred to in regulatory documents, there is a dearth of case studies to help guide microbiologists and Quality Assurance departments. This article presents three case studies. While the specific issues may or may not be of direct relevance, the areas examined and the thought processes will be of wider applicability.


Sandle, T. (2022) Tracking and tracing to the root cause: case studies in microbial contamination, European Pharmaceutical Review, April 2022:


Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (

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