From the outbreak of Zika virus to advances in Alzheimer's treatment, 2016 has shifted the public debate on health, bringing new opportunities as well as a series of threats. Researchers have struggled this year, as well as during the past ones, to bring answers to the most important questions when it comes to the health and safety of the population.

1. The Rise And Fall Of Zika Virus

Severe birth defects in isolated places have exploded into a full-blown crisis once the Zika outbreak was documented. While the virus was first identified back in 1947, it only reached the health spotlight in 2016, after starting to affect children in 2015.

What makes this virus difficult to fight is the lack of symptoms. At best, there are some scarce indicators, such as fever or headaches, which can be easily attributed to other causes, leaving the people affected by it with very few choices concerning the identification of its installation in the body.

The virus takes the form of microcephaly in children, which translates into smaller heads than normal. The condition can have detrimental cognitive effects on the patients, and it can negatively affect the quality of life. Thousands of such children were born with this condition, and there is still no vaccine against Zika. However, the Centers for Disease Control and Prevention have issued numerous recommendations for people who are in danger of catching the virus.

As of Nov. 18, Zika is no longer a global emergency, according to the World Health Organization.

2. The Consumption Of Opioids, An Increasing Issue

Much has been written about the higher number of people who have turned to opioids and prescribed medicine. The number of people who died because of synthetic opioid overdose has more than doubled in the past 16 years.

In response to these rates, by which, according to the CDC, over 2 million people across the United States use opioids for nonmedical reasons, safety recommendations have been issued. The CDC proposed new prescription guidelines in order to lower the drug abuse, which have received support from the Attorneys General.

"Drug overdose deaths and opioid-involved deaths continue to increase in the United States. The majority of drug overdose deaths (more than six out of ten) involve an opioid," noted a CDC statement on the opioid epidemic.

3. The End Of Ebola Outbreak

Very much like the Zika virus, the WHO declared that Ebola is no longer an issue of global emergency. The virus affected areas in Western Africa specifically, among which Liberia, Guinea and Sierra Leone registered the most cases. During the outbreak, more than 11,000 people died, while over 28,000 were infected.

However, the virus is no longer internationally dangerous, and it does not represent a global threat.

"The Ebola outbreak in West Africa is no longer a Public Health Emergency of International Concern. However a high level of vigilance and response capacity must be maintained to ensure the ability of the countries to prevent Ebola infections and to rapidly detect and respond to flare-ups in the future," noted  WHO Director-General Margaret Chan.

4. Advances In Alzheimer's Treatment

While Alzheimer's is one of the most merciless cognitive disorders, it is beginning to be understood by the scientific community.

In August, a research was published about a new experimental drug, called aducanumab, which is believed to be a potential candidate to treating this disease. There is still no definite cure of the disorder.

However, progress in research now allows medication to alleviate many of its symptoms, although it has not been reversed up until now.

This new drug could be proven effective if it meets two crucial standards: the first one lies in its capacity to distinguish between toxic forms of amyloid proteins and benign ones and only target the first type, and the second one is enhancing the capacities of immune cells located in the brain. The latter would help to the process of toxin removal.

5. Measles Eliminated In The Americas

2016 was also the year when endemic measles was eliminated from America, according to the WHO. The issue was all the more important as the disease accounted for a large number of deaths among children across the world. Approximately 134,000 deaths were attributed to the disease in 2015.

According to the WHO, the best way to prevent the disease is to vaccinate. Vaccination alone resulted in a 79 percent drop in the overall number of cases worldwide from 2000 to 2015. Due to the fact that the disease is so contagious, the organization recommends that every country has 95 percent of the population vaccinated in order not to spread the virus.

6. Marijuana And Referendums

The election day was also the day of referendums for people in many states across America. Five states voted for the legalization of recreational marijuana. These were Nevada, Arizona, Maine, Massachusetts and California. Additionally, other 21 states allow using the drug for medical purposes.

But the election day didn't only mean ballots for voting the president and the legalization of marijuana. Some states also held referendums about a series of other public issues. For instance, four states including California, voted for gun control.

It was a big day for California. Aside from gun control, another referendum, which was carried out the same day addressed death penalty. Two other states also conducted referendums concerning this public issue.

7. Smokers Turned To Vaping

Electronic cigarettes were on the rise in 2016, according to a CDC report.

"Current cigarette smoking is at an all-time low, which is great news. However, it's troubling to see that students are engaging in new risk behaviors, such as using e-cigarettes. We must continue to invest in programs that help reduce all forms of tobacco use, including e-cigarettes, among youth," noted CDC Director Tom Frieden, M.D., M.P.H. in the statement.

The flavors in e-cigarettes make them more toxic, according to a study. Moreover, the power voltage of the electronic cigarettes was also linked to a higher toxicity.

"These findings have important regulatory implications, because the features of e-cigarette products – such as the power of the device and the presence of flavorings – can be regulated and standardized," noted the author of the study, in a press release.

While e-cigarettes are dangerous and represent a public health hazard, especially for young people, the overall number of people who smoke traditional cigarettes is at an all-time low, which gives health representatives hope when it comes to the effects of awareness campaigns.

8. Male Birth Control: Tested And Rejected

Due to the fact that contraceptive methods are significantly less varied for men than women, aside from condoms, withdrawal and vasectomies, there is not much that men can do. Researchers have come to the conclusion that safer contraceptive methods should be produced, since in 2012 approximately 40 percent of the total number of pregnancies were accidental.

However, a new method, consisting of hormonal shots, got rejected despite the trials proving that it was roughly 96 percent effective.

"Although the injections were effective in reducing the rate of pregnancy, the combination of hormones needs to be studied more to consider a good balance between efficacy and safety," noted study co-author Dr. Mario Philip Reyes Festin in a press release.

9. CRISPR Gene Editing Could Potentially Cure AIDS

Gene editing is an essential procedure when it comes to curing a number of diseases which are now considered deadly, among which are AIDS and lung cancer. A research team from UC San Francisco employed the gene editing technology in order to modify genetic codes.

A high number of studies have been conducted since the 1980s in order to cure HIV. However, this pivotal method mutated gene molecules, which are strains of the HIV pathogen. Once these genes are inactive, they could block the HIV strain.

This research progress is considered to be a milestone when it comes to treating the deadly disease which accounted for more than 18,000 diagnoses in 2015 alone.

10. Sugar And Soda Non Gratae

There have been a series of reports in 2016 concerning health policies suggesting fiscal measures when it comes to unhealthy products, such as sugar and soda. Due to the nutritionally unhealthy lifestyles of people across the United States, government and health representatives have started to wonder if a formal intervention is necessary.

"Fiscal policies that lead to at least a 20 percent increase in the retail price of sugary drinks would result in proportional reductions in consumption of such products," noted the WHO report.

Lowering the overall intake of free sugars would mean ingesting less calories, which would reduce the obesity rates, a rising problem within the United States. Concerning taxing soda, Philadelphia has become the first city to formally introduce such a measure. The purpose of this regulation is to reduce consumption, which would lower the obesity rates.

Additionally, there already are companies which have thought of the mechanisms of public health. For instance, Nestle managed to create a way to use less sugar in its products. The method involves augmenting the sugary taste in smaller amounts in order to reduce the overall quantities used in producing the sweets.