1. Reliable enumeration of malaria parasites in blood films using digital image analysis

Quantitation of malaria parasite density is an important component of laboratory diagnosis of malaria. Microscopy of Giemsa-stained thick blood films is the conventional method for parasite enumeration. Accurate and reproducible parasite counts are difficult to achieve, because of inherent technical limitations and human inconsistency. Inaccurate parasite density estimation may have adverse clinical and therapeutic implications for patients, and for endpoints of clinical trials of anti-malarial vaccines or drugs. Digital image analysis provides an opportunity to improve performance of parasite density quantitation.

Accurate manual parasite counts were done o­n 497 images of a range of thick blood films with varying densities of malaria parasites, to establish a uniformly reliable standard against which to assess the digital technique. By utilizing descriptive statistical parameters of parasite size frequency distributions, particle counting algorithms of the digital image analysis programme were semi-automatically adapted to variations in parasite size, shape and staining characteristics, to produce optimum signal/noise ratios.

A reliable counting process was developed that requires no operator decisions that might bias the outcome. Digital counts were highly correlated with manual counts for medium to high parasite densities, and slightly less well correlated with conventional counts. At low densities (fewer than 6 parasites per analysed image) signal/noise ratios were compromised and correlation between digital and manual counts was poor. Conventional counts were consistently lower than both digital and manual counts.

Using open-access software and avoiding custom programming or any special operator intervention, accurate digital counts were obtained, particularly at high parasite densities that are difficult to count conventionally. The technique is potentially useful for laboratories that routinely perform malaria parasite enumeration. The requirements of a digital microscope camera, personal computer and good quality staining of slides are potentially reasonably easy to meet.

2. What is hemoglobin and it?s role?

Hemoglobin is the protein molecule in red blood cells that carries oxygen from the lungs to the body's tissues and returns carbon dioxide from the tissues back to the lungs. Hemoglobin is made up of four protein molecules (globulin chains) that are connected together. The normal adult hemoglobin (abbreviated Hgb or Hb) molecule contains two alpha-globulin chains and two beta-globulin chains. In fetuses and infants, beta chains are not common and the hemoglobin molecule is made up of two alpha chains and two gamma chains. As the infant grows, the gamma chains are gradually replaced by beta chains, forming the adult hemoglobin structure.

Each globulin chain contains an important iron-containing porphyrin compound termed heme. Embedded within the heme compound is an iron atom that is vital in transporting oxygen and carbon dioxide in our blood. The iron contained in hemoglobin is also responsible for the red color of blood. Hemoglobin also plays an important role in maintaining the shape of the red blood cells. In their natural shape, red blood cells are round with narrow centers resembling a donut without a hole in the middle. Abnormal hemoglobin structure can, therefore, disrupt the shape of red blood cells and impede their function and flow through blood vessels.

Anemia symptoms and how is hemoglobin measured?

Anemia is a medical condition in which the red blood cell count or hemoglobin is less than normal. Symtoms of anemia include: Fatigue, feeling of unwellness, heart palpitations, hair loss, shortness of breath. Hemoglobin is usually measured as a part of the routine complete blood count (CBC) test from a blood sample. Several methods exist for measuring hemoglobin, most of which are done currently by automated machines designed to perform different tests o­n blood. Within the machine, the red blood cells are broken down to get the hemoglobin into a solution. The free hemoglobin is exposed to a chemical containing cyanide that binds tightly with the hemoglobin molecule to form cyanomethemoglobin. By shining a light through the solution and measuring how much light is absorbed (specifically at a wavelength of 540 nanometers), the amount of hemoglobin can be determined.

What are normal hemoglobin values? The hemoglobin level is expressed as the amount of hemoglobin in grams (gm) per deciliter (dL) of whole blood, a deciliter being 100 milliliters. The normal ranges for hemoglobin depend o­n the age and, beginning in adolescence, the gender of the person. The normal ranges are:

·  Newborns: 17 to 22 gm/dL

·  One (1) week of age: 15 to 20 gm/dL

·  One (1) month of age: 11 to 15 gm/dL

·  Children: 11 to 13 gm/dL

·  Adult males: 14 to 18 gm/dL

·  Adult women: 12 to 16 gm/dL

·  Men after middle age: 12.4 to 14.9 gm/dL

·  Women after middle age: 11.7 to 13.8 gm/dL

All of these values may vary slightly between laboratories. Some laboratories do not differentiate between adult and "after middle age" hemoglobin values. Pregnant females are advised to avoid both high and low hemoglobin levels to avoid increasing risks of stillbirths (high hemoglobin-above the normal range) and premature birth or low-birth-weight baby (low hemoglobin-below the normal range).

A low hemoglobin level mean? A low hemoglobin level is referred to as anemia or low red blood count. A lower than normal number of red blood cells is referred to as anemia and hemoglobin levels reflect this number. There are many reasons (causes) for anemia. Some of the more common causes of anemia are:

·  Loss of blood (traumatic injury, surgery, bleeding, colon cancer, or stomach ulcer),

·  Nutritional deficiency (iron, vitamin B12, folate);

·  Bone marrow problems (replacement of bone marrow by cancer);

·  Suppression by red blood cell synthesis bychemotherapy drugs;

·  Kidney failure;

·  Abnormal hemoglobin structure (sickle cell anemia or thalassemia).

What does a high hemoglobin level mean? Higher than normal hemoglobin levels can be seen in people living at high altitudes and in people who smoke. Dehydration produces a falsely high hemoglobin measurement that disappears when proper fluid balance is restored. Some other infrequent causes are high hemoglobin levels are: Advanced lung disease (for example, emphysema), certain tumors, a disorder of the bone marrow known as polycythemia rubra vera.

What is sickle cell disease? Sickle cell disease is a genetic condition in which the quality of hemoglobin is defective. This condition can cause abnormal hemoglobin that can result in abnormally-shaped (sickled) red blood cells (see illustration). These abnormal red blood cells cannot easily pass through small blood vessels leading to inadequate oxygen for the tissues of the body. Sickle cells also have a shorter life span than normal red blood cells (10 to 20 days compared to 120 days). This rapid turnover may result in inadequate time to replace the red blood cells and may result in anemia.

In sickle cell anemia, o­ne defective hemoglobin gene is inherited from each parent. If o­nly o­ne gene is inherited from o­ne parent, then the condition is milder and referred to as sickle cell trait. Symptoms of sickle cell anemia vary depending o­n its severity. Patients with sickle cell trait may experience mild, if any, symptoms at all. In sickle cell disease, symptoms are more significant, especially in episodes of acute crisis. These symptoms can include:

·  Generalized body aches and pain

·  Chest pain,

·  Bone pain

·  Shortness of breath,

·  Ulceration of skin,

What is thalassemia? Thalassemia is a group of hereditary conditions with quantitative hemoglobin deficiency. The body's failure to make globulin molecules will lead to a compensatory mechanism to make other less compatible globulin molecules. The different types of thalassemia are defined based o­n what type of globulin molecule is deficient. The severity of these conditions depends o­n the type of deficient globulin chain, the number of deficient globulins, and the severity of the underproduction. Mild disease may o­nly present as mild anemia whereas severe deficiency may not be compatible with life.

What is the hemoglobin A1c test? Hemoglobin A1c or glycosylated hemoglobin is a rough indication of blood sugar control in people with diabetes mellitus over the preceding 3 months. As more glucose (blood sugar) circulates in the blood o­n a daily basis, more glucose is bound to the circulating hemoglobin. Normal hemoglobin A1c levels range between 4% to 5.9%. As this number reaches 6% or greater, it signifies poorer diabetes control. A hemoglobin A1c of 6% roughly correlates with an average blood sugar level of 135 mg/dL (milligrams per deciliters) over the previous 3 months. Each 1% increase in hemoglobin A1c above 6% represents an average blood sugar of approximately 35 mg/dL over 135 mg/dL. For example, a hemoglobin A1c measurement of 7% corresponds to an average blood sugar level of 170 mg/dL in the previous 3 months.

How can a person increase his or her hemoglobin level?

There are a number of ways to increase hemoglobin levels. In general, low hemoglobin levels that need to be increased are caused by three circumstances: decreased red blood cell production (for example, altered bone marrow hemoglobin production, iron deficiency), increased red blood cell destruction (for example, liver disease), and by blood loss (for example, trauma from a gunshot or knife wound). Addressing these underlying causes of low hemoglobin levels initially determines what method to use to increase hemoglobin levels.

Methods to increase hemoglobin levels are varied and their use depends o­n the underlying problems. Some of the ways to increase hemoglobin include:

·  Transfusing red blood cells

?  Receiving erythropoietin (a hormone used to stimulate red blood cell production in individuals with decreased red blood cell production or increased red cell destruction)

·  Taking iron supplements

·  Increasing the intake of iron-rich foods (eggs, spinach, artichokes, beans, lean meats, and seafood) and foods rich in cofactors (such as vitamin B6, folic acid, vitamin B12, and vitamin C) important for maintaining normal hemoglobin levels. Such foods include fish, vegetables, nuts, cereals, peas, and citrus fruits.

Individuals should not take iron supplements or other treatments for low hemoglobin levels without first discussing such treatments with their physician as side effects from these treatments and/or excess iron intake may cause additional problems. Also, iron supplements should be kept away from children as iron poisoning in young children can be fatal.

3. What is hepatitis and How to prevent?

Hepatitis refers to an inflammatory condition of the liver. It?s commonly caused by a viral infection, but there are other possible causes of hepatitis. These include autoimmune hepatitis and hepatitis that occurs as a secondary result of medications, drugs, toxins, and alcohol. Autoimmune hepatitis is a disease that occurs when your body makes antibodies against your liver tissue. Your liver is located in the right upper area of your abdomen. It performs many critical functions that affect metabolism throughout your body, including:

·  bile production, which is essential to digestion

·  filtering of toxins from your body

·  excretion of bilirubin (a product of broken-down red blood cells), cholesterol, hormones, and drugs

·  breakdown of carbohydrates, fats, and proteins

·  activation of enzymes, which are specialized proteins essential to body functions

·  storage of glycogen (a form of sugar), minerals, and vitamins (A, D, E, and K)

·  synthesis of blood proteins, such as albumin

·  synthesis of clotting factors

According to the Centers for Disease Control and Prevention (CDC), approximately 4.4 million Americans are currently living with chronic hepatitis B and C. Many more people don?t even know that they have hepatitis. Treatment options vary depending o­n which type of hepatitis you have. You can prevent some forms of hepatitis through immunizations and lifestyle precautions.

The 5 types of viral hepatitis

Viral infections of the liver that are classified as hepatitis include hepatitis A, B, C, D, and E. A different virus is responsible for each type of virally transmitted hepatitis. Hepatitis A is always an acute, short-term disease, while hepatitis B, C, and D are most likely to become o­ngoing and chronic. Hepatitis E is usually acute but can be particularly dangerous in pregnant women.

- Hepatitis A: Hepatitis A is caused by an infection with the hepatitis A virus (HAV). This type of hepatitis is most commonly transmitted by consuming food or water contaminated by feces from a person infected with hepatitis A.

- Hepatitis B: Hepatitis B is transmitted through contact with infectious body fluids, such as blood, vaginal secretions, or semen, containing the hepatitis B virus (HBV). Injection drug use, having sex with an infected partner, or sharing razors with an infected person increase your risk of getting hepatitis B. It?s estimated by the CDC that 1.2 million people in the United States and 350 million people worldwide live with this chronic disease.

- Hepatitis C: Hepatitis C comes from the hepatitis C virus (HCV). Hepatitis C is transmitted through direct contact with infected body fluids, typically through injection drug use and sexual contact. HCV is among the most common bloodborne viral infections in the United States. Approximately 2.7 to 3.9 million Americans are currently living with a chronic form of this infection.

- Hepatitis D: Also called delta hepatitis, hepatitis D is a serious liver disease caused by the hepatitis D virus (HDV). HDV is contracted through direct contact with infected blood. Hepatitis D is a rare form of hepatitis that o­nly occurs in conjunction with hepatitis B infection. The hepatitis D virus can?t multiply without the presence of hepatitis B. It?s very uncommon in the United States.

- Hepatitis E: Hepatitis E is a waterborne disease caused by the hepatitis E virus (HEV). Hepatitis E is mainly found in areas with poor sanitation and typically results from ingesting fecal matter that contaminates the water supply. This disease is uncommon in the United States. However, cases of hepatitis E have been reported in the Middle East, Asia, Central America, and Africa, according to the CDC.

Causes of noninfectious hepatitis

Alcohol and other toxins: Excessive alcohol consumption can cause liver damage and inflammation. This is sometimes referred to as alcoholic hepatitis. The alcohol directly injures the cells of your liver. Over time, it can cause permanent damage and lead to liver failure and cirrhosis, a thickening and scarring of the liver. Other toxic causes of hepatitis include overuse or overdose of medications and exposure to poisons.

Autoimmune system response: In some cases, the immune system mistakes the liver as a harmful object and begins to attack it. It causes o­ngoing inflammation that can range from mild to severe, often hindering liver function. It?s three times more common in women than in men.

Common symptoms of hepatitis: If you have infectious forms of hepatitis that are chronic, like hepatitis B and C, you may not have symptoms in the beginning. Symptoms may not occur until the damage affects liver function. Signs and symptoms of acute hepatitis appear quickly. They include: fatigue, flu-like symptoms, dark urine, pale stool, abdominal pain, loss of appetite, unexplained weight loss, yellow skin and eyes, which may be signs of jaundice. Chronic hepatitis develops slowly, so these signs and symptoms may be too subtle to notice.

How hepatitis is diagnosed?

History and physical exam: To diagnose hepatitis, first your doctor will take your history to determine any risk factors you may have for infectious or noninfectious hepatitis. During a physical examination, your doctor may press down gently o­n your abdomen to see if there?s pain or tenderness. Your doctor may also feel to see if your liver is enlarged. If your skin or eyes are yellow, your doctor will note this during the exam.

Liver function tests: Liver function tests use blood samples to determine how efficiently your liver works. Abnormal results of these tests may be the first indication that there is a problem, especially if you don?t show any signs o­n a physical exam of liver disease. High liver enzyme levels may indicate that your liver is stressed, damaged, or not functioning properly.

Other blood tests: If your liver function tests are abnormal, your doctor will likely order other blood tests to detect the source of the problem. These tests can check for the viruses that cause hepatitis. They can also be used to check for antibodies that are common in conditions like autoimmune hepatitis.

Ultrasound: An abdominal ultrasound uses ultrasound waves to create an image of the organs within your abdomen. This test allows your doctor to take a close at your liver and nearby organs. It can reveal: fluid in your abdomen, liver damage or enlargement, liver tumors, abnormalities of your gallbladder.

Sometimes the pancreas shows up o­n ultrasound images as well. This can be a useful test in determining the cause of your abnormal liver function.

Liver biopsy: A liver biopsy is an invasive procedure that involves your doctor taking a sample of tissue from your liver. It can be done through your skin with a needle and doesn?t require surgery. Typically, an ultrasound is used to guide your doctor when taking the biopsy sample. This test allows your doctor to determine how infection or inflammation has affected your liver. It can also be used to sample any areas in your liver that appear abnormal.

Treatment: Treatment options are determined by which type of hepatitis you have and whether the infection is acute or chronic.

Hepatitis A:Hepatitis A usually doesn?t require treatment because it?s a short-term illness. Bed rest may be recommended if symptoms cause a great deal of discomfort. If you experience vomiting or diarrhea, follow your doctor?s orders for hydration and nutrition. The hepatitis A vaccine is available to prevent this infection. Most children begin vaccination between ages 12 and 18 months. It?s a series of two vaccines. Vaccination for hepatitis A is also available for adults and can be combined with the hepatitis B vaccine.

Hepatitis B: Acute hepatitis B doesn?t require specific treatment. Chronic hepatitis B is treated with antiviral medications. This form of treatment can be costly because it must be continued for several months or years. Treatment for chronic hepatitis B also requires regular medical evaluations and monitoring to determine if the virus is responding to treatment. Hepatitis B can be prevented with vaccination. The CDC recommends hepatitis B vaccinations for all newborns. The series of three vaccines is typically completed over the first six months of childhood. The vaccine is also recommended for all healthcare and medical personnel.

Hepatitis C: Antiviral medications are used to treat both acute and chronic forms of hepatitis C. People who develop chronic hepatitis C are typically treated with a combination of antiviral drug therapies. They may also need further testing to determine the best form of treatment. People who develop cirrhosis (scarring of the liver) or liver disease as a result of chronic hepatitis C may be candidates for a liver transplant. Currently, there is no vaccination for hepatitis C.

Hepatitis D: No antiviral medications exist for the treatment of hepatitis D at this time. According to a 2013 study, a drug called alpha interferon can be used to treat hepatitis D, but it o­nly shows improvement in about 25-30% of people. Hepatitis D can be prevented by getting the vaccination for hepatitis B, as infection with hepatitis B is necessary for hepatitis D to develop.

Hepatitis E: Currently, no specific medical therapies are available to treat hepatitis E. Because the infection is often acute, it typically resolves o­n its own. People with this type of infection are often advised to get adequate rest, drink plenty of fluids, get enough nutrients, and avoid alcohol. However, pregnant women who develop this infection require close monitoring and care.

Autoimmune hepatitis: Corticosteroids, like prednisone or budesonide, are extremely important in the early treatment of autoimmune hepatitis. They?re effective in about 80 percent of people with this condition. Azothioprine (Imuran), a drug that suppresses the immune system, is often included in treatment. It can be used with or without steroids. Other immune suppressing drugs like mycophenolate (CellCept), tacrolimus (Prograf) and cyclosporine (Neoral) can also be used as alternatives to azathioprine for treatment.

Tips to prevent hepatitis

Hygiene: Practicing good hygiene is o­ne key way to avoid contracting hepatitis A and E. If you?re traveling to a developing country, you should avoid: local water, ice, raw or undercooked shellfish and oysters, raw fruit and vegetables. Hepatitis B, C, and D contracted through contaminated blood can be prevented by: not sharing drug needles, not sharing razors, not using someone else?s toothbrush, not touching spilled blood.Hepatitis B and C can also be contracted through sexual intercourse and intimate sexual contact. Practicing safe sex by using condoms and dental dams can help decrease the risk of infection.

Vaccines: The use of vaccines is an important key to preventing hepatitis. Vaccinations are available to prevent the development of hepatitis A and B. Experts are currently developing vaccines against hepatitis C. A vaccination for hepatitis E exists in China, but it isn?t available in the United States.

Complications of hepatitis: Chronic hepatitis B or C can often lead to more serious health problems. Because the virus affects the liver, people with chronic hepatitis B or C are at risk for: chronic liver disease, cirrhosis, liver cancer.

When your liver stops functioning normally, liver failure can occur. Complications of liver failure include: bleeding disorders, a buildup of fluid in your abdomen, known as ascites, increased blood pressure in portal veins that enter your liver, known as portal hypertension, kidney failure, hepatic encephalopathy, which can involve fatigue, memory loss, and diminished mental abilities due to the buildup of toxins, like ammonia, that affect brain function, hepatocellular carcinoma, which is a form of liver cancer, death.

People with chronic hepatitis B and C are encouraged to avoid alcohol because it can accelerate liver disease and failure. Certain supplements and medications can also affect liver function. If you have chronic hepatitis B or C, check with your doctor before taking any new medications.

4. Promising malaria vaccine tested

An international research team has conducted successful phase II clinical tests of a new anti-malaria medication. The treatment led to a cure in 83 cases. The new combination of drugs was developed by Professor Peter Kremsner of the Tübingen Institute of Tropical Medicine and the company DMG Deutschen Malaria GmbH. The study was recently published in Clinical Infectious Diseases and is freely accessible.

In the study, the researchers tested the efficacy, tolerability and safety of a combination of the drugs Fosmidomycin and Piperaquine. The twofold medication was administered for three days to patients aged o­ne to thirty who were infected with malaria via the Plasmodium falciparum pathogen. In the 83 evaluable cases, there was a 100% cure rate. Patients tolerated the treatment well, and it led to a swift reduction of clinical symptoms. Safery issues were limited to changes in electrocardiogram readings, as had been described for Piperaquine.

The study was conducted at the Centre de Recherches Médicales de Lambaréné (CERMEL) in the African country of Gabon; CERMEL has close ties with the University of Tübingen. Financial support came from the nonprofit organisation Medicines for Malaria Venture (MMV). "This study represents a milestone in the clinical research into Fosmidomycin," says Tübingen Professor of Tropical Medicine Peter Kremsner. The substance was originally extracted from Streptomyces lavendulae and today can be produced synthetically. It blocks a metabolic pathway for the production of Isoprenoid in the malaria pathogen. This makes the malaria pathogen unable to metabolize or reproduce. Because Isoprenoids are formed via a different synthesis path in the human body, humans have no target structures for Fosmidomycin. For this reason humans tolerate the drug well and suffer barely any side effects. In addition, this unique mechanism excludes the possibility of cross-resistance to the drugs used in earlier malaria treatments.

The new combination meets WHO guidelines for combination therapies. The two drugs mechanisms against differing target structures means that they attack the parasite in the bloodstream independently of o­ne another. This meets WHO requirements for a fast and effective treatment of the acute phase of infection, and for protection against relapse due to reappearance of the infection. The researchers say the effective mechanism helps to delay the formation of a possible resistance. Further studies are in planning to optimize dose.

5. How to tackle drug resistant parasites that cause killer disease malaria

A new analysis of all relevant previously published clinical data shows how parasites causing malaria become resistant to a commonly used treatment for malaria in travellers. This insight may help recognise when resistance arises and therefore reduce the risk of its spread. The malarial parasite Plasmodium falciparum is spread by mosquitoes when they suck blood from people. Infection with Plasmodium spp. is a major cause of mortality worldwide.

In 2015, there were 149 to 303 million clinical cases of malaria, resulting in between 236 and 635 thousand deaths. Most cases are in endemic countries, although malaria is also o­ne of the most frequent causes of morbidity in travellers returning to non-endemic countries. Experts at St George's, University of London say their research shows that a standard combination of drugs: atovaquone and proguanil (Malarone®), which is commonly used to treat P. falciparum malaria in travellers provides a potentially cheap alternative to artemisinin-based combination therapies (ACT), which are the current frontline antimalarial option for treatment in areas of malaria.

Malarone® is notable for having fewer side effects than other, older antimalarial drugs. As the combination is now free from patent it should become a more cost effective treatment option.

Dr Henry Staines, a lecturer at St George's, said: "This study really provides an overall understanding of how well this drug combination works based o­n the research available. "Doctors treating patients need to know they can use this drug combination effectively and know what to look for o­n the odd occasion when this treatment fails. "It also provides important information to scientists so that they can determine future research efforts and protect this important resource, as we strive to eradicate this dreadful global disease."

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